Everyone has to accept Bamber is guilty. The evidence has convicted him & several appeals have failed. Most of the evidence Bamber has not disputed.
It would still be a good idea for Bamber to request a fingerprinting test. It could be arranged secretly by his legal team. If the results were good it could be annonced in the media. If not, only his inner circle knows he had it.
I suspect he would pass, as he did the lie detector test. He is ruthless enough to be able to not show emotion when asked questions.
1) its not about emotion
2) your other comments about keeping tests private are your assumption and not based on any credible source
3) as you say he is guilty and serving time why on earth would you think the test a good idea?