First, is understanding of evolution “vital” to the understanding of biology? No.
Pretty deep contrast to the often quoted sentiment of geneticist Theodosius Dobzhansky:
Nothing in biology makes sense except in the light of evolution.
McLeroy continues making bold, absolute statements with no support.
Next, has evolution been demonstrated to be true beyond any reasonable doubt? No.
Is evolution’s support from the peer-reviewed literature unassailable? No.
I might be charitable and assume that he was unable to expand how he arrived at these conclusions -- which again are at odds with mainstream biology -- due to space limitations. I'm not sure how charitable I feel, though.