Fair enough - the last time I used an Objet 2 shot part was probably ~5 years ago, and at the time the materials were not very good, and had very bad flexibility (usually flexing would cause them to delaminate from the substrate) - but it’s good to hear you’ve had better luck with it. Of course that’s ensuring that the shore rating of your RP part is able to be similar to that of your real part (otherwise it would be tough to get match the testing).
I think the bigger concern in my mind is that without seeing the OP’s actual design, without any engineering support on the design of the ribs, spacing of the compression elements, etc it can be a bit of a crap shoot.
I was not implying that any tool would be done on the first try, but I was implying that if this is a new area for their design, it is worth spending the extra couple of thousand on a mechanical engineer with experience in sealing design. Especially for IP67 which is very challenging (even with a full team of ODM and internal ME’s we would spend weeks debugging and carefully modifying the tools and design to meet IP67 - and it was standard for most of our products).