Cruz and his cronies are talking guff. All that is planned is for a pointless contract with no practical impact to be allowed to expire. "What exactly will happen if ICANN doesn't get its way by September 30?" Nothing of the least practical importance will change, and -- Kieren, I'm talking to you -- this isn't what ICANN wants, it's what all the technical communities (names, addresses and protocol parameters) have wanted for years.
There's nothing Congress can do anyway - even if they wasted their time passing a law at this late stage, the President would certainly veto it. By the time a new Administration gets into the White House, it will be too late. Thank goodness.
It's true that ICANN is flawed. Once the silly US Govt contract is out of the way, the technical communities will be free to tackle the flaws.