IHeartMedia’s decision to cut a deal with Mario Gabelli’s Gamco Asset Management Inc. may push the end of the radio company’s bankruptcy past February, senior lenders said in a court filing Dec. 10.

IHeart had been scheduled to seek final approval of its reorganization plan this week, but put off that court hearing to finalize a deal to settle a shareholder suit with Gamco, according to court papers.

The settlement would end the lawsuit Gamco filed against officers of iHeart’s...