In his first two years perhaps he could have negotiated and got more wall built. But Trump did not build a coalition for his wall. He is a CEO type and not a politician. The things that everyone loves about him (non-politician) can also be his weaknesses. It takes teams to win and Trump is a team of one and maybe a few more.
Now? Not happening. It comes down to votes. Trump just doesn’t have them.
He may as well issue an executive order if he wants something done on the wall.
He has said he is building the wall while working on getting more funding. He can’t negotiate with people who do not want to negotiate. The national emergency approach is in the works. He said he will get it done.. one way or the other.. I have every reason to believe him.