You've got yourself into some confusion here. Your iTunes Store page is at
https://itunes.apple.com/podcast/river-of-life-alliance-church/id1028499779
It's looking for a feed at
http://www.riveroflifegj.com/?feed=seriesengine&enmse_pid=2
which is basically empty - although its 'lastPubDate' is today it has no episodes. The feed you have linked to - at the same URL but with pid=3 on the end - works fine when subscribed to in iTunes, though it does indeed fail validation in Podcasts Connect. The Store is showing the state of the pid=2 feed at the time it could last read it.
When I open the pid=3 feed in FireFox, my default RSS reader, it works OK and looking at the coding there it appears to be OK. However when I submitted the feed to FeedValidator it rejected it, and the coding isn't for the feed at all but for a web page containing an iframe. This suggests that the server is detecting the client (program) which is requesting the feed and serving up different coding for an RSS reader or for a web page reader, and evidently serving the wrong version to Podcasts Connect. These problems can arise when you get to complicated with the server; ideally you just want a straightforward link to the feed file and no frills.
Presumably Series Engine, whatever that is, is messing things up for you. As the feed works perfectly well in the iTunes application the coding may work in the iTunes Store if you can change the URL to the pid=2 version which the Store is expecting. Otherwise I can't advise on Wordpress or Series Engine, or say why something which worked before is now a mess.
