I noticed that my dishwasher was displaying an error message that looked something like ERuu. Anyway, it won't stop heating.
From what I've read, I am thinking that it might be a thermostat problem.
So, am I on the right track?
Also, are there two thermostats on this unit? If so, where are they located.

Any and all help is much appreciated.

Thanks.

Awesome!!
I can't wait to get started.
Can't thank you enough.
I'll keep you posted.
Thanks Again.

What does all of this mean?
It means the unit is going to be a pain.
The ERuo and the #1 diagnostic point towards the Fan assembly. See Page 12 in the manual.
The kicker is #3 in the diagnostics points towards the hall sensor (speed sensor) in the motor.
Perhaps try running the manual controls on Page 18 in the manual, though I am not sure that these will run on your unit.

I would check/clean the fan/vent assembly wiring

Does it still appear to be the thermostat?
No the diagnostics do not point towards a heating problem.
But never hurts to check things.
The Hi-limit thermostat Item 29 in Section 7 should be 0 ohms at room temperature.
The heater should be around 16 ohms.
I could not find a temperature to resistance spec for the thermistor, perhaps I just missed it.
I would say the above is a long shot.

I am going to stick my neck out here and say I believe it is the control board. My reasoning here is that the all errors you see are related to sensor inputs to the board and I doubt that 2 of the sensors would fail at the same time.

I would look closely at P2 on the board as this plug is common to the motor and the fan and the thermistor assemblies. A bad/dirty connection here could cause all your problems.

I also ran the tests on page 18 and here are the results.
Everything passed, except the "Test Variable Speed motor functions 1 - 4. They all resulted in 00.
A definite fail here.
If the motor was running then the board is not receiving the speed feedback from the motor.

The Vent / Fan Dry resulted in a 20+. Is that acceptable?
Not sure about this. If the fan was running, it may be OK.

The Thermistor resulted in 84 degrees. Is this acceptable?
This looks normal.

When the unit originally started having problems did the motor run?

I tried to find more info on the motor but ran into a brick wall.
It has a diode inside which makes it a DC motor and then a tach (hall) feedback but could not find a wiring diagram for it so you could check it.

I hate replacing parts without knowing for sure that they are blown.
Sometimes you have no choice but to replace the most likely and see what happens.

In this case since we see problems in different sections of the unit my gut says the control board is at fault.

Look around and see if you can find a supplier that will let you return the parts if it does not help.

Hopefully someone else will jump in with a more definitive answer.