"Too Stupid for Words" award?
Yes, descent can mean "a decline in" as well as one's ancestral lineage, but then evolution means "a change or development in" and does not inevitably mean progress. Better adapted is not better overall. So not only does the descent in The Descent of Man not mean what Heidi make it out to, it would not contradict evolution even if it did.
Incidentally, Heidi means 'noble one', so this person can't even write her name without contradicting herself.