Compounded across 50k years, there's only a very, very, very tiny sliver of possible conditions where the meat was just barely thawed enough to be contaminated,

Compounded across 50k years, there's only a very, very, very tiny sliver of possible conditions where the meat was just barely thawed enough to be contaminated, but not enough to be simply entirely rotted away 49k+ years ago. If it exists to be frozen at all, it is virtually guaranteed to have been frozen the entire time. Another example of scaling being counterintuitive.