With me the solderless thing was laziness after rewiring an old Harley.
Now the new kit which arrived yesterday has to be soldered .
Pots come in two flavors. Linear and logarithmic.
Volume controls on radios are logarithmic because that is how we hear.
Maybe you got the wrong kind of pot.
I also see mention of solderless connections on the forum threads.
When I was servicing communications equipment a lot of the time a problem would be a cold solder joint. Reheating the connection was usually all that was required. My advice is to stay away from solderless connections. Just my 2 cents.