General Discussion

47 CFR 76.938(e) --Right to reject programs. No license shall be granted to a television broadcast station having any contract, arrangement, or understanding, express or implied, with a network organization which, with respect to programs offered or already contracted for pursuant to an affiliation contract, prevents or hinders the station from:

(1) Rejecting or refusing network programs which the station reasonably believes to be unsatisfactory or unsuitable or contrary to the public interest, or

(2) Substituting a program which, in the station's opinion, is of greater local or national importance.

While the first test would, imo, be hard for Sinclair to satisfy since it apparently is willing to air Kimmel if he makes an apology and gives a donation -- and therefore its decision isn't based on the content itself, the second test is so broad that I'm pretty sure that the FCC would rule in favor of Sinclair if it claims that the news content it is going to put on in place of Kimmel is "in the station's opinion" of greater local or national importance,