No Trump wasn't gaslighting. He even gave credit to the Choice Act by saying:

"So we passed something that hasn't been that recognized, and yet I would put it almost in the class with Choice. Almost in the class with Choice. VA Accountability -- passed. And now, if people don't do a great job, they can't work with our vets anymore. They're gone," Trump said.

The Choice Act didn't provide for firing bad employees within the VA. That part of the act was fought against by the government union employees therefore it didn't make the cut. What's the use of trying to improve a system if you can't get rid of bad actors. This was just one area that plagued the success of the Choice Act which has been beleaguered with problems since it's implementation as they had no means of controlling those who were causing the problems to begin with. The unions also fought eliminating the mileage distance as they seen this as a means to a way to privatize the system, there was some compromises made on both sides but Trump didn't take credit for the entirety of passing the Choice Act just improving upon accountability. Once again you fail to look at the "over all facts".