I mean, those games were pulled during the beta. It doesn't look like nvidia, who should know they'd need that approval before even testing, bothered to try.
There should have never been a, "We found out that we can't use our paid service to provide cloud gaming for third party software with their own, separate TOS/EULA" moment. This should have never made it past their first legal review, and should have been flagged with a plan to address before any serious work began.
Which still speaks to, "Nvidia either didn't know about this, which is monumentally stupid on their part, or were hoping to slide by unnoticed, which is also monumentally stupid on their part."
Absent more details from nvidia, or a clear statement from actiblizz, I just don't see any other read on the situation.
That's literally part of the point of legal teams, who are heavily involved in writing TOS/EULA agreements. If they're not combing over those for potential publishers titles on their list, then they shouldn't be employed as a lawyer, and especially not for a major company like nvidia.
And they didn't "ask", they straight up did it. And only stopped when companies started asking them what the fuck are they doing and probably threatening to take their asses to court if they didn't knock it off ASAP. Nvidia isn't a company they necessarily want to piss off, there are extensive hardware partnerships with publishers, but it's also not a company that they're going to let push them around.