Sounds like McCarthy doesn’t want to do an impeachment inquiry, but most of the house and like 90% of the Americans on the right do.
While there is no requirement to have a vote, he may still have one. What happened if that’s voted down in the house? Do you think people will accept that “well, that’s the end of it”?
He is between a rock and a hard place, when he knows that people want this impeachment inquiry, but also feels there is a chance that it may not pass a house vote. There is a chance he may break that promise.
There is also another option, and that is to skip the impeachment inquiry altogether and just move straight to the impeachment vote, as pelosi did in the case of trumps second impeachment.
Why do people think you have to have evidence before doing the inquiry? The purpose of the inquiry is to look for evidence. If you had evidence, there would be no need to even do the inquiry.