I’m using Torsocks 2.3.0 and DiG 9.20.1

It could be the exit node that you’re using perhaps? Maybe you could try specifying a different exit node and trying again. Also check exit node policies to make sure DNS is allowed, although as your problem only seems to be with MX records then that might not be the cause.

I’ve just tried this (Tor version 0.4.8.12) and it seems to be working fine for me. I’ve tested with both 8.8.8.8 and 1.1.1.1.

…We did not want to contact FlyCASS first as it appeared to be operated only by one person and we did not want to alarm them. On April 23rd, we were able to disclose the issue to the Department of Homeland Security, who acknowledged the issue and confirmed that they “are taking this very seriously”.

I think the owner of FlyCASS was sufficiently alarmed!