You're looking for a definitive answer and I don't think anyone here can provide that. I think that @SundayInSalem answer is excellent: you're on solid ground and should file that way. But don't be surprised if you hear from NY. Don't worry about that until it happens, but be prepared. The fact that your employer stopped NY withholding is a good sign.
That said, reading between the lines, it appears that you did move to TX for your convenience. The fact that the employer has offices in TX, that you support, helps your case. But the fact that you don't work at those locations hurts. If you physically go to those offices, on occasion, would help. But if your "support" is all from home and could be done out of NY would hurt.
