I found the exact file for your TV, and decoded it with ccf2efc. It uses Device=3 the same as most JVC TV's. The commands posted in the discrete section for JVC TV's are also Device=3, commands 29=On and 26=Off. These are the standard discrete power commands throughout the JVC line. (other types of equipment just use different device codes).

So, I would say either you did something wrong in putting those commands in your Pronto or that particular model does not respond to discrete power commands.

-Jon