Candy CDC668: Warms a little, stuff stays wet

Hello,
We have a Candy CDC668-SY that we got used from a friend. When she gave it to us, she said it only dried the clothes at the “Bone Dry” setting (the three Suns on the dial). It was free and we had no dryer, so we took it.
We found that the Two Suns setting was what worked properly, so we left it at that setting for two years, occasionally cleaning the condenser filter, and always emptying the water reservoir and the door filter.

Last week it stopped drying at all; clothes would come out wet. Doing some tests, we found that in the first 5-10 minutes, the clothes got ever so slightly warm. After that the heater must be disengaging because after a while there is no warmth. This was consistent after multiple tries.
I had no multimeter at home (it was at the office, it was a sunday, and we needed the dryer working ASAP!), but looking at the shape of the heater, and seeing it was relatively cheap to order a new one with new thermostat (and thermal fuse? not sure, but there are two things on the heater that look similar) attached.

The heater/thermostat part came, I installed it, cleaned out all the lint around everything inside.
Now, the dryer will run, but the same problem. This time i was touching the back panel where the heater is covered, and for those first 5-10 minutes it gets warmish. But never hot. Then it gets cool again.

I’m thinking there are other thermostats inside, in fact I’m almost sure there are from reading all about dryers these past few days, but I have no idea where to look for them inside. I’ve only found the user manual for this dryer, no service manual.
Either this or a problem with the logic board and/or knob? But that is a more expensive part and I don’t know how to test that either.
Any recommendations? Thank you!

N