Lately I have encountered a problem while sculpting a model created using photogrammetry. When I was using dyntopo to fix areas with wrong topology, newly created faces didn't dynamically unwrap and because of it there are black, not unwrapped spots on my mesh. What I tried to do was using clone brush, but as you may have guessed it didn't work at all because of the texture islands being randomly spread in the image. Also there is a significant part of environment textures which are useless and occupy image space. Here is one of four images used for texturing (just to show what they all look like, posting an image which is the most light-weight): I'd be grateful for any tips on how to fix these black spots.
Thanks in advance