I'm not here to argue. Just offering my opinion. This would have bothered me more when I was younger. Now I've come to realize this from other perspectives. When all else fails, read the contract. Should the coach lie, probably not. But I doubt that anyone besides the coach really knows the truth and you might be assuming things that aren't true.
1) A coach probably shouldn't have jobs at different schools at the same time (and I really doubt that he/she did, perhaps there were verbal plans/commitment but they were likely not employed at two places simultaneously).
2) Whatever school the coach is under contract to work for is where he/she should put their focus. I know nothing about coaching contracts, but schools probably make sure that they extend through signing day for exactly this reason (so the coach can't bail out at the last minute and cause problems for the recruiting class).
3) The coach's contract probably restricts them from discussing plans to leave a school while they are under contract. You can't really expect them to answer that question honestly (other than to say no comment, but that in itself could be seen as an indication that they are leaving).
4) It would also be dishonest to the school that they work for (and to the recruiting class to a certain degree) to start discussing an issue like the coach leaving the school late in the recruiting process. That would certainly be detrimental to the school that they work for and to a certain extent could cause a lot of conflict for recruits.
I'm sorry for your situation and that you feel hurt by the process, but what would you have the NCAA do? Coaching changes are very common and they have to have policies to deal with it. If anything they are protecting the student athletes to a certain degree by deterring them to transfer (which would typically be detriment to completing their degree).