Arlene, there could be a connection. However, I don’t believe it is possible that your Johnathan Allen is a descendant of Isaac B. Allen, son of Abram Allen. Abram had a brother, Jonathan., but he would be a different Jonathan as well. I have a good descendency list of both men and don't have any Collins or Chadwick descendants. Abram left Jefferson Co. about the time of his marriage and ended up in Wisconsin and Jonathan left around 1838 for Illinois.
I am assuming your are referring to Jefferson Co., NY where the Allen brothers were from. Their father left Jefferson Co. as well. I don't know about the other brothers, but they probably left too. There were several Allens in Jefferson Co. at the time. Have you looked at the Jefferson County GenWeb? Kaye