316K Eagles vs 150 confirmed deaths due to windmills over a decade.
So yes, they're wrong. And amplifying this sort of thing is exactly what those campaigns hope for, so you're doing their work for them. You're in good company, Donald Trump did the exact same thing (and made up a number to go with it rather than to claim 'vast' numbers).
Does it mean that any numbers of Bald Eagles killed by windmills is acceptable? No, of course it doesn't. But either we have a different idea when we hear the word 'vast' or 'vast' is exaggerated.
edit: here is an article to back this up:
https://www.newsweek.com/fact-check-are-thousands-bald-eagle...