Always better to turn back when not sure - and you can regroup once you are in known territory. I did the Geronimo trail once, before the fire (from the top down), and it was rather faint then. Lots of trees down, and a faint path, but I do seem to recall it does pretty much follow that ridge down.
If you look at the actual track, it closely follows the route that the map shows:
Which does show it heading down that ridge. Although it is a steep trail, I hope it hasn't been lost in the fire - that would be a shame. It is a "shortcut" - I did a loop starting at the Northern Elk Lake Creek trail, up to Welcome Lakes, then down Geronimo to Mother Lode and back to Elk Lake Creek where we started. It was a nice loop, although rather long. But without it, there is not much of a loop opportunity in that area.