I've had this happen twice now. I have a Gravity form that gets filled out generating a CPT entry. I'll come back later and custom post types generated from that form, are deleted. I've checked the database to see if for some reason they're just not displaying on the front end - but that's not the cased. They are being deleted.
The form entries are still there - but the custom post that was generated is gone, making the plugin unreliable at best.
In fact, I haven't had a single form entry made that has persisted as a CPT. For the sake of troubleshooting, I have made several CPT entries directly (not via Gravity Forms + CPT) and they persist.