>has a significantly better fully laminated display

Sure - but that was one of the reasons for the delay. Jolla decided that they didn't like the original included display. It isn't that they designed in that 'significantly better fully laminated display' at the outset.

And different USB connectors? Oh, please that's hardly a design difference either.

Color and material definitions? Again, not a significant design difference.

The question was whether there was any evidence that the tablet was someone else's design. I'd say the evidence is pretty damning. Jolla themselves admit to at least sharing the design. And even so I suspect they were being economical with the truth.

And let's look at the practicalities. It would be much quicker and cheaper for Jolla to start with a reference design and modify it a bit than to design a tablet from scratch. Given their financing and primary focus on the OS, what do you think they would have done?