“Safek Kohanim? That doesn’t make any sense. I mean, it does, but no one since the before the Chasam Sofer and R’ Akiva Eiger have held that Kohanim were actually Safek Kohanim. We assume our Kohanim are real Kohanim and that a Ksav Yichus is just a Chumra by doing the Avodah. Otherwise we wouldn’t do Pidyon HaBen.”
I asked my rov a while ago he told me since they are only safek it does not warrant saving a life. I got an email from another Rabbi saying the same thing. I asked another rov about giving a kohen kedima in tzedaka and he told me not to so as well. The email gave me these sources: See “Shulchan Aruch” Y.D. 251:9 and “Aruch HaShulchan” 11 there. R’ Tam on Taz 128:39 and others i can look back at the email if you want