Update May 12, 2021: I have quarterly service and heard some scurrying overhead the other day. They sent Alex out to check my attic for mice or other things up there. When he came, he saw evidence that there had at some time been some burrowing up there, but didn't feel it was ongoing. He also checked the crawl space and areas outside of the house to look for signs. Though he is confident I don't have a huge problem on my hands, he put some bait pouches in the attic and will check to see if they've been tampered with when he returns for his quarterly service.
