So, small update, a bit after I posted this (which was after I moved the CheckMK virtual machine to our second ESXi host (it was on the first one)) the connection timeout issue moved to our third ESXi host. Both hosts that have connection timeouts seem to have SQL servers installed on them, so it might be a problem with the server not being able to respond quickly enough when there is a lot of load from the SQL servers.
Would that help narrow down a cause ? I simply masked the site name, IPs and name of computers, sorry if it makes it confusing, had to be done 
P.s., just in case, that’s from the host that just started timing out, both should be configured the same!:
