score:3
There are connections, you can find plenty of them on e-podroznik.pl. Most (all?) of them are the same:
It takes 2-3 hours depending on the connection and there's a train leaving Gdańsk. Total price is 28 PLN (around 6€).
Both websites that you mentioned only look for trains and they're not aware that there are buses going to Łeba, that's why you weren't able to find any connection.
Upvote:1
Check https://www.e-podroznik.pl/
I see plenty of options there with a connection in Lębork.