i see you have lots of advice on this one.

first, i used to live in Tahoe and my ex sold fireplaces and woodstoves there.

that said-

call an expert. they need to inspect your chimney to make sure its 1. clean (so you don't have a chimney fire 2. can draft properly

then you need to figure out if when they converted it to a gas fireplace if they screwed anything else up. also you don't want to throw wood in there and have the gas lines explode (duh)

i'm sure you can get this working, but it will likely require some professional assistance.