These aren't things you have to answer, just some thoughts of mine and a few things I would possibly do - though I know I can't say that for sure. I've always said missing (especially for this long) can sometimes be worse than death of the person.
Are the police talking to the immediate family, giving updates at all?
I have thankfully never been in this situation, so I'm not sure how much family's know compared to the small amount the general public seems to know.
How confident are the cops with the time stamp on the video?
That part just seems so out of place with the other pieces.
Is there working video of comings and goings out of the garage?
I know you mentioned about what sparked the early investigation. I don't think it's a hangup, because the cops have said no foul play so far. Unless they're just not being truthful about that part and that's okay. I just wonder if they would tell family the reasoning.
Have they been able to determine where and when her phone last pinged?
Does family have access to her phone records or computer? I think combing through those may give some answers. Search history in her computer browser. All dating apps to go back and look at messages sent and received for at least the past month. Could even be someone with a fake profile pic (I've known exes to do things like that).
I listened to the Nancy Grace podcast, April 29th, "Paralegal Mom, 26, vanishes, tot son left at daycare. Where’s Denisse Reyes?"
Info of what LE is doing to find Prisma. Below is part of the podcast discussion.
NG asked David Mack (Syndicated Radio Host) what LE has been doing and he replied, "LE has gone door to door, canvassing the entire apartment complex that is attached to the parking garage where we saw her on the video at 5:50 in the evening. They canvassed the neighborhood, they have talked to everybody, every family member, co-worker, past co-workers. They have talked to everybody, it is an exhaustive search. They have knocked on every door."
NG: "You said Everything has been done. I assume they searched bodies of water, if there is one nearby. They brought in tracker dogs, cadaver dogs, scent dogs, shoulder to shoulder search. Have they done drone and air search as well Dave Mack?"
Dave M: "What we have been told by the police, thus far, is that they have done an extensive search around that apartment complex of that 3500 block of Roseland Avenue, which is where her vehicle was found, which they refer to as abandoned, and where that video was taken of the CC camera that we saw. They have gone to every apartment building, every apartment they have knocked on doors. They have gone to the other buildings,along that same block knocking on doors to talk to anybody that has any information about the evening Prisma was last seen. They have asked talked and asked everyone to check security cameras in hopes of finding more footage of her."
They have a bad feeling about Prisma being at the ex boyfriend's apartment complex and knowing their relationship ended badly.
Crime Stories with Nancy Grace