Does this mean that the old Scenic Ridge Route is closed?
I'm not sure .. but my guess is there are not many scenic ridge routes in the area that are open. Unless you mean Angeles Crest Highway, which isn't anywhere near this fire. It's on the south side of the 14 freeway and miles further east.
The surviving section ends at Castaic Lake, off the 5. This fire's to the south and east of that quite some distance. The other fire's to the east of where the north end of the Ridge Route ends near Quail Lake.
The Ridge Route's a really interesting drive and brings back memories of going over it in the days when you had to watch out for runaway trucks. There was one gas station north of Gorman located right at a bend in the road. I think the thing was wiped out several times between '48 and '60. We used to stop there, go to the edge and stare at the wreckage in the canyon below. Now THAT was entertainment!