I am not sure if this is any help to the Daniel Cook researchers but I will offer it up:
Daniel Cook was in the Prince of Wales American Volunteers, also known as General Browne's corps. Early in the war men were taken from this regiment and put into Emmerick's Chasseurs. On one of the muster rolls for Emmerick's there is a John Cook that was shown as one of General Browne's men.
It is highly possible that this John Cook is a relative of Daniel. If you have info on the possible family of Daniel before the war, you may want to see if the family has a John and Daniel. May be a hint.