Not normal but it says flawed quality. That’s probably a veneer that isn’t totally adhered to the plywood. Similar to an air bubble on poorly installed wallpaper. Somebody s/h been more careful selecting a flawless piece. But no, not normal. I think you are entitled to a do-over since somebody selected flawed material. One thing they can do is sand the flaw away so flaw disappears, but then it means that particular spot will be thinner and more susceptible to effects of weather (humidity or dryness in the room). It is not the end of the world but I wished somebody had noticed it b4 painting or when wood was initially installed.

Hmmm.....don't think so. I wouldn't be happy with it.

Did he install the paneling or just the trim on top. It appears to be either a low grade paneling or the vener is delaminating.

Edit: I agree with bossy but sanding may or may not work. If the veneer is thin one could end up with a hole if sanding completely removed the top layer of veneer.

Thank you so much for the replies! I really do appreciate it. I'm trying to get the guy to come back and redo them. Wish me luck!

That’s why knowledgeable pros use MDF or MDO for large flat painted pieces. You get delamination of ply when painted with water borne products in far too many cases.