First of all did you file a --notice to owner--? That is alway the first step in a situation like this. You file notice to owner BEFORE you start work, this tells the property owner that you , the contractor has been hired to do services on his property, it is a very common thing done and is not looked upon coursely. Doing this will protect you from not getting paid, especially if the money is coming from any sort of State funded project.. You need to file intent to dispute payment with the University immediately. You need t make sure that the main contractor or the sub does not get paid before a valid attempt to satisfy your invoice has been made. When you send this letter make sure to imply that you will not sign off on a release of lien, however if payment is made in principle that you will sign a partial release of lien. And that being done a full release of lien is made by the cashing of the check.
And remeber that there are very specific laws that dictate how you MUST get paid from a municipality, government and in most cases a UNIVERSITY that recieves any sort of puplic $$
Playing the breakdown game is easy, break it down any way you want, but make it clear in writting that ALL larbor and material MUST be provided by you solely.