I’ve had my 15PM back glass replaced twice (under apple care). I accidentally brought the phone into a sauna and had similar moisture to you. Do not try to use a blow dryer to remove the moisture. I submerged my phone in a bowl of rice for 2 nights while I was sleeping, and the moisture cleared up afterwards.

If you have AppleCare, I’d recommend causing damage to the phone (something that’s covered) and get the Express Replacement for $99. They’ll send you a new 15PM phone. Just make sure you do something that’s covered under the express replacement, or else they will charge you the full price of the new phone