The GOP should've stood their ground. They got nothing in the deal at all.
They got nothing in the deal precisely because they created a situation where a deal had to be struck to begin with. They would have gotten more of what they wanted if they had just shut up and passed a clean CR in the House to begin with.
Instead, they picked a fight they couldn't win and made promises to their supporters that they couldn't keep, all on the assumption that the president would simply throw up his hands and allow his biggest accomplishment in office to be killed off and that in the polarized legislature we have they could get enough Democrats on board to override a veto.
If you think this had any chance of working, you, sir, are a profoundly stupid man - as stupid as the House members who drank Ted Cruz's Kool-Aid to begin with.