Except at the edges, the fabric could fly at 100+ feet.

I want try this here to see how feasible it is for co trolled environmental spaces.

Well, yes. But there’s still a ton of edges. My initial comment was flippant, but the problem was serious. If it breaks, how would you find out?

Release a bunch of balloons into the air. They'd float to the leak.

If you want to get fancy, coat them with a glue that bonds to the ceiling material, and they'd fix the leak too! At least temporarily. My first thought was that they'd clog the hole automatically even without glue, but I think the pressure differential would just squeeze them through.

Barometric drop. Sufficiently sensored membranes would allow you to triangulate holes.