I threw together this sample app because I wanted to experiment myself with how to allow different edits by different users within a single app. It took me a bit longer than I expected but I was learning some of the new Glide features along the way.
I believe there are others examples out there that do similar things but again there is a difference in looking at what someone has done and doing it yourself. That said this is not a tutorial but the best way to test this is in the Glide builder.
I would suggest that you change the signed in user a few times to random emails and enter in a few expenses for each.
Then you need to change the signed in user to see the full affect of the admin feature. Start with firstname.lastname@example.org. If you set the signed in user to any of those admin emails the image will show. And when you select it will open to the Reimbursement sheet, which in detail view allows admins record payments. So make a copy of the template and hack away at it.
It is not polished at all, just a sort of proof of concept and starting point to experiment further.