I think he's done. He'd have a hard time getting guests to interview at this point. He'll need to close out the operations of his show, an independent operation. I suspect he'll live out the remainder of his years in seclusion.
Rose could start his own online streaming show. He'd interview all of the "alleged" sexual aggressors. There's a long list. "Tonight on the program we have Genius Hollywood Producer and sometimes misunderstood Harvey Weinstein."
The way PBS works, I'm sure there are lots of options available throughout the system. The advantage Charlie had was it was co-produced by WNET and it came with its own funding. I imagine WNET will be looking for ways to tap into that funding base quickly with a replacement. Charlie's show covered a wide range of topics from politics to entertainment. That takes a special kind of host, but there are quite a few name hosts available in NYC.
Howard Stern ??
Isn't he about 75 now? My thinking is that he was near retirement, anyway.
The only real issue that I see here is that PBS may have some interviews "in the can" which they may not be able to air now. But we will see.
There's a guy in the alley near 52nd street, in a trenchcoat, that has some copies...