Update in case anyone else runs into this:
Turns out even though I was getting an error saying it couldn't delete the scans they were actually getting deleted. Same thing happened with trying to Launch a scan, I'd get an error stating it was already in use, yet it would get scanned.
In the end this turned out to be an issue with only on Firefox. Works fine in IE 6-8 and since Firefox isn't officially supported in MVM 7 I'll just have to deal with the nonsensical error messages until it's officially supported in a future release.
Thanks Cathy for helping me out on this.