If anyone is interested, the following ST code runs with just a few changes:
Aside from changing a few physicalgraphs, there is a RunEvery1Minute that based on my logs appears to run MANY times a minute (?hundreds?), so every 5 minutes is fine for me. It also has some quirky behavior for determining if the device is on (it will query the TV, but will send an off event and then an on event if the TV is on so the event log will be filled with off and on events. I changed it so that it only updates if the state has changed. All I wanted this device driver to to was to power the TV on or off, and it does that and can change inputs as well, among a few other things. Very handy for these relatively inexpensive Roku TVs (I have Costco's Hisense model, but works for others such as TLC).