I doubt it is that easy. The trust is an entity. I would expect it has its own tax number and files taxes. The parents are a beneficiary, not the owner. They really have no say in what happens with the trust. I think you need to go to court to break/dissolve the trust. This is usually AFAIK is because the trust can't fulfill it's purpose.So if the grantors (your mom & dad), the trustee, and the beneficiaries all agree and sign off on the liquid trust assets being used for the CCRC and the trust is dissolved, who in the world will object? Since the trust will never be used to try to dodge paying for nursing home care, it's as if it never happened. If you're all in agreement and just did it, I'm not sure what the legal peril would be... who would object and sue the trustee?
You're probably right that no interested party would object if the trustee violated the trust terms and just paid for the parent's LTC. But all risk would be on him.
One would also need to look at tax consequences. This is not like a revocable trust where the owner can pull assets out because they are owned by them.
Now the question could the trust create earning so they had to be distributed? That could make cash flow unless the trust also says it can't be used for LTC.