Sorry, but I am just trying to point out your "inconsistencies" (so to speak) before you actually try to attempt it with CBP. Probably you have not dealt with CBP a lot, and you can expect to get asked the same type of questions that I am asking here. If a stranger on the internet that does not have anything to do with CBP sees some inconsistencies, you can bet CBP has seen that movie before, too. I know you have all the intentions to do things the right way. I believe in you. CBP does not have any obligation to do so, and will make a decision based on the answers you give them when attempting to enter. The first thing they try to pick is inconsistencies such as the one you have presented here.
CBP will also make those assumptions.
You are under no obligation to explain it to me or anyone here, but since the purpose of your trip is to do some research, it has EVERYTHING to do with your questions. Otherwise, if you were not doing this research, this trip would not happen (at least that's my understanding based on how you have presented your facts).
Sorry if I hurt you. I am just trying to help. Good luck with everything.