I finally talked to the property management guy, after having left three voice mails for him to contact me. In the first one, I was cheerful, in the second one, I was cordial and in the third one I was annoyed. He almost instantly called me back, and I hate that I couldn't get a timely response when I was still feeling friendly.
So the good news is that he was totally open to my just sending him the receipts for reimbursement from Rotor Rooter. Zero argument; he didn't even seem interested in hearing about it. I'll stick them in the mail and get that going.
Even if I wouldn't have been reimbursed, I am still glad that I took matters into my own hands and got it fixed. Knock on wood: no problems since.