Both deer look fully mature to me.
They are, but at our lease, any buck over 8 points needs to be at least 6 1/2 to be cleared to take it.
Then I'd want to see more photos before making the call on the 12 pt because I can't make him 6 1/2 from that one photo. The 6 pt. needs the air let out of him ASAP. Enter your local deer contest if they have a six point category. He might win it.
I honestly think that deer is over 6.5 think he is 7.5 plus, But it hard to make that call on a deer with no history on.
He isn't a protein hound deer nor protein heavy area.
Need more photos. But as of now post mature, knees a scared and muscles are degrading in the rear. Not something you see on 4-6 year old deer IMO