Your problem is GoDaddy...

If you go to a proper host you will not have these problems. We manage a LOT of sites that use Merchant center (about 50) and we have a CRON that automatically updates and sends the feed.

A proper host will know what ports to open, and allow the feed to be sent.

People at GoDaddy probably don't know what a "port" is, or if they do, they probably think you are talking about ships.