Ok, let's look into it. (you can also send me your printer.cfg if you want)
The Mini e3 v3 has the following switchable outputs:
HB - PC9
E0 - PC8
FAN0 - PC6
FAN1 - PC7
FAN2 - PB15
Keep in mind that they all switch ground only. 24V is always there.
You can use all of them for whatever you want, Klipper is very flexible here. HB is your heated bed, no questions here. E0 should be connected to your Hotted board HE0.
I don't know which of the fans on your board does what, you may need to connect them all and see which one does what (I guess your hotend does not have 3 fans). in the end you want [hotend_fan] to be the one calling the hotend (not the part!). the [fan] will be controlled by the slicer (overhangs, bridges and so on).
DCIN on your board should ideally be connected directly to the PSU, you do not want it to be switched.
An exclamation mark (!) inverts a pin. The other symbol (^) enables a pull up resistor on a pin, which is needed for things like endstops or buttons. These can also be combined.
PB0 is just the name of one pin. PC0 would be a completely different pin.
Different Microcontrollers have different naming conventions, that is why you sometimes see names like PB10 and on other controllers it might be GPIO10.
So how would that work? You can not distinguish between commercial or private use, because the traffic is encrypted, you don’t know what is transmitted, that is the whole point.
Maybe you didn’t raise it enough? It is definitely the sign of being too close to the bed.