mx1.dreamhost.com has no TXT records.
Question and response
Question
dig mx1.dreamhost.com. TXT
Answer
The response has no answer records.
Authority
dreamhost.com. 300 SOA ns1.dreamhost.com. hostmaster.dreamhost.com. 2026022504 1995 1800 1209600 300
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0