The point of doing the above is to find out why it's failing, not to perform a single invocation. If it completes successfully, then it's very likely that something is wrong with your configuration of cron itself. (Yes, that'd be unusual if it happens on 3 different servers, but it's possible.)
Centova Cast's cron jobs are configured in /etc/cron.d/centovacast. Check the cron jobs listed in that file and make sure they're ALL showing up in /var/log/cron (or /var/log/messages if you're on Debian) at the correct intervals.
We *have* had reports of problems with CC's cron jobs, but two of the three clients who've reported it and insisted it was a CCv3 bug have provided their root login details to me personally, and I was able to log in and confirm that in both cases it was their own fault. (The first, strangely, didn't even have cron installed, and the second had a broken cron configuration that was causing some jobs not to run.)