I would think that such signing bonus would offset some of the Browns money he is due, so unless a team is offering a total salary package of more than that $4.5 M it shouldn't effect things, I could be wrong.
Captain brought up an interesting point. If a team shoves some of the money out into the future, are the Browns off the hook? Not sure, but really what OBJ is probably looking at, in regards to money, is what he ends up with, not who is paying it. Although, I'm sure he would love to stick it to the Browns.
I think that is a part of why he is delaying his decision to ponder his options. Does he go where there is more upfront money, but maybe not as good of playing situation? Or go to a team like Green Bay, for less money, but potentially a better playing situation and a possible shot at a SB ring?