A problem was detected with TrueDepth camera. FACE ID has been disable

So I fell in some water and my iPhone 12 was completely submerged for a few minutes. I dried it out in some rice overnight but FaceID has stopped working. Apple wants £200 to fix it which seems a lot for an old phone.

I read and article on ifxit.com saying it's impossible to repair the Dot Projector ? TrueDepth camera not working after water damage, any hope? -

"Unfortunately, the dot projector seems to be one of those parts that are particularly susceptible to water damage and ultimately non-repairable. Well, at least not for us average joes. There is one guy, Phyrne, that seems to be associated with the rework company REWA that has fixed one, but man, it's way beyond what most of us can do. "

My question is how do I know if the water damage hasn't damaged the infrared camera, proximity sensor, flood illuminator, ambient light sensor, speaker, microphone, 7MP camera or Dot Projector?

Next question what do these "Re-progammers" do that I keep hearing about online?