What I understand reading the manual is that when pluging in a pedal, the knob position is the lowest value the setting can meet.
Meaning that with your EP2-3 plugged, the knob will be operational if the pedal is full-heel.
You are probably using a ts-cable to connect the cv from the 101 env to the freq-CV input of the 102?
Connecting a ts-cable into one of the CV-inputs shorts the power at the ring contact of all the other inputs, and therefor, the expression pedal does not work anymore. If you want to use them together, use a trs-cable to connect the 101 with the 102 (it’s in the manual actually).