Isn't the only entity that could conclusively determine if the agreement has been violated the very one who would violate it?

It seems unlikely given that Amazon has been rapidly scaling up the services they offer, with some of them conveniently taking the form of companies who run their entire operation on AWS (i.e. Twilio with AWS Contact Center).

If somebody can prove me wrong, however, that would be lovely :)

Regardless though, expecting Amazon to refrain from taking the proprietary information they have access to (in any form) and drilling you into the ground with their own twist on it seems like a bad bet, just ask Nucleus.