Before spending hundreds of $$ on a new touch pad control board, I certainly would give the old one an extra chance... if your board is the same as the one shown on the pic below, then I count several components that might cause your stoves strange behaviour:
1: Dirty potentiometers. I count three including the small trimmer. Contact cleaning spray ( available in all electronics shops ) will most likely make those pots work as new again. Note: The red auger on/off switch for the pellet feed may also need some cleaning to ensure a rock solid connection.
2: Leaking electrolytic capacitors. I count two above the ICs at the bottom of the pcb. Carefully write down the capacity, voltage rating and polarity. These caps are very cheap... only a few $.
I hope you are handy with a soldering iron or else visit the nearest tv/radio repair shop and bring the technicians some cookies/cakes for their coffee break... then I'm sure they will help you
3: I count three Triacs on the pcb... two with heat sinks ( for the blowers ) and one without heatsink ( for the augermotor ). These are most likely standard types available for a few $ in your local electronics shop. Since it's only your room blower that runs on high when it shouldn't, only the Triac for this blower needs replacement, but as a precaution I would change both blower Triacs.
4: The bypass relay is the square shaped block with a transparent plastic cover. Write down what's written on it and do a Google search... it's most likely a standard type still available and if not, some pin-to-pin substitute version with the same specs should be possible to find. Well assorted electronics shops are generally very helpful in such cases.
Also, the molex connector and all solderings on the pcb board should be inspected with lamp and magnifying glass and cleaned and possibly resoldered.
I would start by cleaning the three pots, the slide switch and the molex connector and if that doesn't help... replace the components as suggested above.
I'm convinced that you can make your rotary knob control board as new again and enjoy the heat from your Whit for many years to come.
Good luck and keep us posted