[DiasExMachina]

That assumes some nefarious evildoers rubbing their palms in giddy delight about how their wicked plans have been so perfectly set.

So on that, I believe you are jumping the gun. In the end, they don't own your setting, so the worst they can do is terminate your license. Nowhere did I get the impression they would chase a company down for abandoning 4ED and going to another system. I am fairly certain WOTC did not create a "no take backsees" rule, lest we have all fallen into tall grade school