You and I will agree to differ on this point. No FBS FB team, no Rent. So a full accounting uses the true cost, not any sweatheart rental agreement.
Absent an executed agreement, the norm is for property owners (or their agent. In this case, Global Spectrum) to be responsible for debt service and maintenance. GS can certainly use rents and fees to offset debt service and maintenance, but the tenant does not necessarily have discretion over what costs their rent covers.
In the meantime, I did do some digging. Per UConn's response to the Big XII:
d. Athletics department budgets; debt levels, debt service obligations, and repayment timing and amounts (last 5 years and projected).
The Athletics Department incurred debt related to the construction of Harry A. Gampel Pavilion. The final debt payment of $89,422 will be made in FY2017. There is no other direct debt obligation for the department...
Further down in the document:
h. Investment in athletic facilities (last 5 years); contracted or planned capital expenditure projects and funding sources therefore.
...(Pratt and Whitney Stadium at Rentschler Field) was financed and built by the State of Connecticut, and is being leased back to the university, which has been paying the majority of the debt service via that agreement.
So, while UConn does not own Rentschler Field, their response to the Big XII, presumably as the anchor tenant, indicates they are responsible for a significant portion of debt service.
On the other hand, according to the New London Day, the bonds floated by the State used to finance it will be paid off in 2020 and in the remote possibility that UConn downgrades football, it will be a non-issue.
I still will not agree to disagree because you made an off the cuff SWAG. Plus there is no indication that UConn is responsible for maintenance. In fact, the Rentschler financial statements clearly state that,
"...income generated by the operations of the Stadium to be used for the purpose of funding maintenance and capital improvements at the facility."