About his walk.
I was a nurse and my husband was a prosthetist (fabricated and fit artificial limbs) and I worked with him in his clinic over 10 years.
BG looks like he could possibly be a below the knee amputee on the right. A B/K prosthesis is usually held on by suction created by the stump fitting into the socket of the prosthesis. If the stump is extremely short, it is held on by a sleeve.
When he steps, the right pant leg has a telltale crease right under the knee. This is created when the lip of the prosthesis, or the top, catches on the material of the pant. It also happens when there is some slippage of the prosthesis. A lot of amputees wear baggier pants "cover" the prosthesis but this can lead to that crease.
When he picks up his left foot to take a step, you can see the sole of his shoe in the toe area because that's how most of us walk...heel to toe, meaning on the up step, our ankle flexes up to bring the toes up and to allow us to "land" on our heel first. He does that perfectly on the left.
When he raises his right leg, he raises it a bit higher and straight up, the sole of the shoe in the toe area cannot be seen at all, even as he brings it down. That's because their is no ankle flexion at that time. He brings it straight down. Not heel first, his whole foot comes down at the same time.
It's very subtle, and most people have no idea someone is a below the knee amputee but I caught that right away.
Number 1 reason people lose a limb is diabetes/circulation problems. Then trauma...motorcycle, car, tractor, lawn mower, industrial, etc. accidents. We of course have many vets with amputated limbs also.
A prosthetist usually takes care of the same person for life unless they move. It's very personal, and patients are extremely loyal to their prosthetists. If they sent the new sketch to every clinic in the nation, and he IS a below the knee amputee, his prosthetist would recognize him.
I sent my thoughts regarding the above to the tip email address of the state police.