So there are double (DU) lionesses who will have x2 the cubs right? With the max being 8. What if we apply that same mutation but to males, and males with double scrotums/balls will always have or guarantee 4 cubs from a lioness and 8 cubs from a DU lioness.

Another one can be a BALLESS lion, rendering him infertile and ineligible to be a king. We have lionesses who are or can be born infertile so why not a male?

Another mutation can be lions born without limbs. They can be born missing a forelimb or back limb making females unable to hunt and males unable to be king because they can't properly "defend".