My advice is to not send either.
For what it’s worth (and for future people trying to look this up), my daughter submitted her 2 really bad (like, terrible) subject test scores. We were under the mistaken belief that because UC Berkeley requires scores from all your SAT attempts (for the actual SAT w/ Essay), that she needed to send the Subject tests, too.
This is not the case. Once we realized the mistake it was too late, since you can’t cancel reporting after the fact. She addressed the issue in the “further comments” section of the UC application.
In the end, she was accepted into 3 of 5 UCs she applied to. UCB was the only flat-out rejection, & waitlisted at UCSD.
Bottom line, it wasn’t a deal breaker to send them, but avoid the stress & regret of sending in less-than-awesome scores if you can.