I found this post which is the same issue I have with same provider I am using, I get that maybe their SMTP setup is rubbish, but it works with other clients so it seems like emClient should have some way to work around this, be it an explicit timeout override or something else.
You can see in the initial error logs, and pretty much anyone elses error logs that it waits 30 seconds from the send to timing out, and I imagine other email clients just wait longer. I guess regardless if emclient cant support slow email servers I cant use it 
as other clients work with it, and I don’t understand why an explicit override value could not be provided in the UI if someone wants to allow for longer timeout durations.