My thinking about the frozen dinners vs the other case described is in the detail of events as they happened.
In the case of Martin, self harm is suspected by some because he left a note about disappointment and going away. He then left his electronics, he left antidepressants, and then he chose to leave. He had a plan.
Specifically, he left underdressed for an overnight stay in the wilderness and he was carrying food that required specific preparation in a microwave. If he was planning on taking a hike, he chose the wrong food. If he was planning on self harm but decided to bring food with him as he walked along the Parkway, lost in the thought of his final decisions, he took the wrong food. If he was planning on all this ahead of staging the note and items in the room, i.e. when he was shopping, he chose the wrong food from the beginning. The frozen dinners means he was preparing for a specific destination where he would have access to a microwave. Maybe at some point beyond that, beyond the life of the provisions he carried, maybe he had a plan for self harm but at least when he left his apartment he had a destination where he expected to stay for a period of time and before we can start thinking self harm, we need to find that destination.
In the scenario mentioned, a man goes to work, eats lunch then is overcome by depression and jumps from a bridge. Maybe he left a note detailing his intentions, maybe he made the decision he would see his colleagues one last time before committing to the act. Either way, when he left, his intention may have been self harm but not before he made his way to an alternate location first (work).
In Martin's case, his choice of food clearly indicates he had a destination with a microwave. His choice of clothes indicates he would not be exposed to the outdoors over night. His choice of footwear might suggest he was not intending on any major trekking else he would wear hiking boots (if he had them). The choice to leave electronics, indicates he did not want to be tracked and wasn't worried what they might find about his motives by searching through the devices. He left a note, though details are withheld, suggest he had some sort of disappointment issues and was intending to be gone a while. As I understand it, it does not suggest self harm. He left his wallet but not his ID, indicating his destination might have required proof of identity to check in to a place or perhaps pick up a transportation ticket. Conversely, if he took the ID with him to help in identifying his body, he certainly wasn't planning on a water borne event which would ruin said ID. Nothing screams self harm to me. Everything points to him having a destination where he would be a while. A destination that required his ID and would have access to a microwave. If the microwave was not a factor then his decision to purchase the food came before the decision to leave and he just grabbed whatever food he could get his hands on when leaving that morning which, to me, is not the action of someone who didn't intend on living long enough to eat it. So, for me he either planned on an overnight stay in a hotel or a home where he could prepare his food, or perhaps a few days on the road as a passenger or even a rehab type setting.
Now let's look at the antidepressants. Was his hairbrush or toothbrush screened for signs of him actually taking the antidepressants?
The presence of therapeutic drugs in the hair of psychiatric patients was investigated, and the method for simultaneous determination of antidepressant and antipsychotic drugs by GC/NPD and GC/MS was also established. Eight different psychotroic drugs were detected from the hair of 32 subjects, and chlorpromazine and clozapine concentrations in the hair were found to be dependent on the dosage and the correlation coefficients were 0.8047 (P < 0.001, n = 16) and 0.7097 (P < 0.001, n = 16) respectively. Segmental analysis demonstrated that there was a correlation between the subject's drug exposure history and the distribution of drug along the hair shaft.
I'm assuming the investigators conducted the screening to identify if Martin was actually taking the drugs they found. Likewise, I'm going to assume the investigators asked his room mates to supply their own hair sample to rule them out as being the prescription owner.
Were Martin's prints found on the container/blister packs holding the drugs?
Without this information we have to give an equal chance at the drugs being placed in his room to bolster the depression angle vs actually being part of Martin's regime.
He dressed light, with a windbreaker. Carried a backpack, easy shorts, easy sneakers, didn't take a bus or an Uber to get where he wanted to go. He walked and aside from the bus footage, somehow avoided all traffic and surveillance camera's. Was that by design or just by luck of the draw? Certainly there were homes and businesses that captured something. No? OK, so by luck of the draw he is not captured by video though was spotted, by two different friends, as he walked outside of town.
The way I see it. The frozen dinners removes so many options for him. We are not talking snacks like granola bars you can eat out on the trail, we are talking about dinners requiring a specific venue to prepare. Dinners that were chosen during his "shopping" trip in preparation for his eventuality.
When he left that morning, it's likely his destination had amenities and if you need amenities, I do not believe the first thing on your mind is self harm. At best, he walked away though circumstances suggest someone has helped.
Hotels, homes, cabins, RV's and semi trucks have microwaves. Which ones also require an ID to gain access? If we arrive at hotels being the destination then we also have to account for the fact that microwaves are not standard at all hotels though are prolifically distributed so is it also safe to assume Martin had some forward knowledge of the hotel room amenities since he was confident he could use the Microwave? So, If we go with this hotel angle, he either had forward contact with the venue or he had the help of someone who told him what to bring.
For me, "frozen dinners" says much more about his destination than trail mix or a granola bar and combined with the other items we have learned, seems to point he had am immediate destination, other than self harm, in mind.