Btw, it sounds like my loadspeaker is malfunctioning after the repair. Has anyone else had this issue? I wonder if it's just some rubbing alcohol that needs to dry up.

After failing to do a battery replacement on my samsung s10+ from ifixit I was worried about trying again but I just did the screen from this guide as well as a battery while I was in there and it seems to have worked great! Thanks so much! The fingerprint reader worked by clicking the link in the last step in this article -- just realize that you have to restart the phone a couple times for it to work.