Viking natural gas oven one burner won't ignite even after switching igniter from L to R and R to L

I have a Viking natural gas range and noticed that the oven burners weren't igniting so I had a repair person come in on Nov 27, 2015 and tell me that I need to replace the gas supply valve (pb010084). They quoted me an obscene amount of money to supply and replace the gas valve so I sourced the part (pb010084) and replaced it myself. The pb010084 did not solve the problem so I replaced both the igniters in December, 2015 and everything has worked perfectly until today.

I noticed that the left bottom burner (left side when facing the oven door) would ignite for a few seconds and then go out while the right bottom burner continued to burn.

Here's what I have done did so far:

1. swapped the igniters by moving the L to the R and the R to the L with the result that both igniters glow, the right bottom burner fires up but the left will not even fire up anymore; and
2. installed the original pb010084 that came with the stove with the result that the right bottom burner still fires up but not the left bottom burner.

I have concluded that the igniters are not the problem since I switched them around a couple of times and only the right side fires up.

Could it be that both the original and replacement pb010084 are defective whereby only the left side is not working?

Any information would be greatly appreciated.

Thank you for reading.

via Viking natural gas oven one burner won't ignite even after switching igniter from L to R and R to L
by audit13