Did you try to add that domain into whitelist in Email--> Email Configuration--> Sending Email--> (below Delivering email-->Domain routing) add that specific domain
hope i could help you.
Thank you for your help.
But I still can't send email to the domains,
by default Your EMail Gateway will try to send any Email encrypted using TLS.
Believe it or not, there are way lot of servers out there that cannon handle encrypted mailtransfer.
Especially when transferring mails to eastern countries You may encounter problems that these server either do not speak TLS at all, or can only handle weak or broken ciphers suites.
So in my eyes this looks like that there is no encryption capability on the target server. So You may want to disable TLS for that specific target domain.
Keep the Wildcard-Record at the very bottom of your TLS exception list, otherwise this will override Your entry as this list is always handled up -> down