I agree with Marriard. This makes no sense. But if your DD is the best pitcher around, you should take the 3 best hitters and go form your own team. A coach who takes 8 pitchers doesn't know what he's doing. That's a 10u rec all-star team, where everyone is a pitcher and shortstop.
No advice. I'm only surprised that this is even a question, but if people aren't in agreement on the definition of 'is', I suppose the definition of 'commitment' should be decidedly fluid, too.
If there was a late cancellation and you're not on their team's call or email list, that could be the explanation as to why you did not find out. I doubt they would deliberately do that to your DD and you.
Not being 'invited to at least go watch' only means that your DD is not their main focus...
As described, what you're talking about is a very common injury that is generally linked to overuse. Hopefully that's all that's wrong. If her doctor doesn't recommend ceasing activity for 10-14 days in addition to a standard treatment regimen, I'd suggest getting a second opinion.
Don't waste any more time with this group. Let the coach know you're taking another opportunity now. If things change, maybe DD can try to land a spot with old coach next spring.