The v2 prototype WAS running the panels at 90 Hz. It had two hdmi inputs and thus was more an pimax 4k hmd x2 from a tech point or more like a 8kx-prototype. So the hmd had two chips to receive two 4k signals (in reality 2x 2560 x1440 max, but i simplified) from the pc.
Only with the v3 came the problem of not reaching 90Hz. Because they switched the hardware to one DP connection now there is only one chip receiving and sending to two scaler chips (i guess here, one per panel). So this receiving chip now has to deliver double bandwitdh. And this is causing the problem not reaching 90Hz reliably.
So the CEO was not lying about the v2 doing 90Hz.
Another question is if they really could deliver the 90Fps stable while running off the laptop. And i think it is save to say that this was not always the case