Missy might have blocked the perp's way; we don't have enough information to say.
IMO, It is fairly easy to disprove the idea that this was targeted now that we have the podiatrists testimony.
If Missy heard someone in the Church when no one should have been there, instead of going towards where the person was in order to investigate, all she had to do was exit the building and call the police. Most people—most women, especially—would have done exactly that.
She had a chance to remove herself from the situation unscathed but didn't take it. No killer who had targeted Missy would have given her that chance.
I don't know whether this perp was there to steal or simply to role play and vandalize, but I am confident that he was not there for Missy.
It must not be that easy if investigators weren't able to rule this possibility out completely.
Some people knew that surveillance in the church isn't working like it should.
Were they making a big deal out of it? Warning everyone who could end up being the first/last/only one in the church at some time to be especially cautious?
If YES - perp could learn about it from same source and use that to their advantage.
If NOT - then apparently people felt relatively safe about it and didn't think of it as a big deal.
Some people knew that Missy will be going there at this time of night to get ready for her classes.
Was that a big deal? Unusual? First time ever?
If YES - she should be advised to have someone to accompany her, someone else than her husband to remind her to be cautious and enter only in a group as students will arrive; reminded that surveillance is there for a reason and place can be not so safe at the time.
If it didn't happen and was immediately taken as super neglectful on the church administration's side or if it happen but Missy ignored it, then it'd be a different story. But nobody really said that it was the case.
If NOT - then she had no reason to be super extra cautious and nervous upon realising that someone else is there.
Everything seems to be hinting that it wasn't THAT big of a deal, and that church is huge: many rooms, multiple playrooms, kitchen, office and so on. Not "just" a church, where there could be literally like one or two people who would have keyes and none who could be there without mentioning it to the others.
Was Missy so well informed and in touch with everyone who had access to the keys to know that 100% she will be there alone, totally no way that someone else may show up at random time to clean, set up a playroom, change decorations or do something? Is there any reason to expect that she was?
It seems to be pretty active community with various activities and events going on. There could be plenty of people (in reality or in Missy's considerations) who could end up having a reason to be there, working on something to get it ready before work, before an event, or before group of kids will arrive.
If Missy heard someone in the Church when no one should have been there, instead of going towards where the person was in order to investigate, all she had to do was exit the building and call the police. Most people—most women, especially—would have done exactly that.
She had a chance to remove herself from the situation unscathed but didn't take it. No killer who had targeted Missy would have given her that chance.
If what she heard would be really scary, omnious sound hinting at someone with ill intent being there, she would turn back and run away. Cause why would she stay and go to investigate unarmed and unaware what's going on. To risk her health, safety and life just cause she could and had nothing better to do?
We don't know what she heard and if it was just a suspicious sound or something that could be easily associated with a person causing the sound. And surely we can't assume that she heard someone breaking things in church while confident that there was no innocent/good reason for someone from the community to be there and just choosed to walk on a crazy cop wannabe doing his late night church cosplay weirdity.
And this is victim blaming.
Either A: cause she was so fierce and confrontational that it could be expected and easily predicted that no matter what, she won't get scared. But if so, then really no reason to leave gun behind.
Or B: cause she had no or not enough reasons to instantly associate the sound or even somebody's obvious presence there with danger.
Most people would exit the building and call cops... if what they heard was scary, alarming and easily associated with something wrong or bad going on.
I doubt that "most people", hearing some sounds in big building, which theoretically should be empty, but was a centre of multiple activities for multiple people, especially not being the owner (or there regularily at that time of day/week) would immediately assume that something bad is going on + not considering the place as being interesting for potential burglars or vandals.
Yes, we know that her husband was concerned enough to insist on her carrying a gun for self protection. But it sounds for me like he was just cautious in general, cause she was getting out at night and alone - not like he was seriously considering that she might be in danger and may actually need to that gun to fight for her life someday.
We don't know what she heard and if it was just a suspicious sound or something that could be easily associated with a person causing the sound. Might be something like opened window, malfunctioning electricity or whatever, followed by
"Is anyone there? Please come and help me, I have an issue with..." to lure her to the exact location where surveillance wasnt recording.