A guy i know who shops a lot of pins has come across a few Speak Easy 4's and a couple of Speak Easy's, 2  player version, which were all imported from Germany.

As we noticed this pf was not wood and what looked to us like some kind of plastic, all were warped in one way.

All of the pins we come across the pfs were immaculate except for one, had a couple of minor wear spots from sinking inserts.

IIRC its the left hand side closer to the top where they would be warped as there is no timber support/rail because one of the mechs is literally on the edge of the pf. It is there where the pf was usually warped.

As an educated guess i am tipping this is the only pin they used this material on, what ever it is...