They look great in pictures

I can see a very slight difference, but, I think, its due to how the light hits one of them, rather than it actually is. In any case, it looks just fine. He did a nice job of staining.

This is from the morning. Is it easier to see?

I asked a door installer to stain a fiberglass french door

Was the installer also a painter? Could you call them back and review the difference with them?

And what you have is a double door. French doors have glass panes extending for most of their length