I think he just steps down as CEO, there is no company acquisition happening, so no one gets paid. I think company essentially failed to generate revenue and/or get new investment round.
Investors are being bought at 2.5B valuation
Base on those numbers, $150M of series A with 1B valuation would be bought now for 375M(which is high for failed startup), my understanding is that such transaction has to be disclosed.
I may be too skeptical, but it is just hard to believe someone (who?) throws 400M (to seed + A investors) plus significant amount to founders into essentially failed startup.