What is the ruling on not paying the remaining university fees and instead using the amount to pay professors' wages for reviewing a research paper, given the lack of sufficient funds to pay both parties?

What is required to be paid to the university must be settled, due to the Almighty's saying: "O you who have believed, fulfill [all] contracts." As for the professors, nothing should be paid to them except when compelled to secure one's right, in which case it is a permissible bribe for the giver and unlawful for the taker.