by Richard Oelmann.
If its in the logs as being sent, then Moodle has definitely sent it (as I understand it anyway!)
That does not prove however that the emails left your email system as that would be a separate entity from Moodle itself.
If the Moodle logs are saying it was sent, there should be logs on your email server that also say it went out from there, so that's probably the next step in the chain to check.