Hello!
The method to compare PTR & MX to domain name is wrong, because it could be correct but different one and aaPanel shows "Not Set".
For example I have two domains: D1.com & D2.com
D1.com with Mail Server = mail.D1.com
D2.com uses the same MX and PRT records as D1.com
aaPanel Don't understand it:
In real check all works by mail-tester:
in /etc/postfix/main.cf myhostname = mail.D1.com