Ah, yes on the first count at least, though that criteria wasn’t on your bulleted list, I guess it was in the title.
That being said, UV breakdown might not be as concerning in the short term if the substance is removed fairly often. I wonder if a clear gelatin or glycerin layer would last long enough?
I’ve also seen resin-infused paper-like substrate layers of material like carbon fiber attempt to bypass the requirement of an FEP. Each print layer was a new sheet and once the print was done the un-cured material was blown away.
But, as far as resistance to UV and immiscability with UV resin, testing would be required, as I’m assuming you intend to replace the FEP film layer with a dense liquid.
It isn’t like their power was just off for the entire time, either. If it’s kicking on intermittently, then that means that the crews are working on multiple issues, done of which aren’t likely to be caught during the initial repair.
You know how long it takes for you to be without power before PSE even considers a refund of a portion of your power bill?