Didn't think about the temp. rating on the valve. Just prior to
reading you email, I read about a stainless steel flex hose that was
black coated for visability and heat protection to 350F.

I used a gas dryer T valve and 3/8" flex hose from Lowes that said it
was rated for alternate uses such as high BTU gas logs. For this
reason I didn't think about high temps.

I can pull the valve and re-install the original 3" nipple with a 1/2"
- 3/8" flare adapter and just use the outside key valve, no problem.
The log installation instructions showed a T valve, and I thought that
in the case of an emergency, it would be easier to shut the gas off
directly at the T and not have to hunt around for the key.