I guess that our early licensees saw the possibility to adopt...

I guess that our early licensees saw the possibility to adopt faster to a new technology when licensing it "overnight" rather than joining an early access program pondering if it'd be a good fit for the strategy and current product roadmap.
Which is understandable. For a large company like Renesas spending 2 or 5 million (don't know the initial fee) additional dollars is not a lot for them, especially when excepting a cost-saving result in the near term already.

Since we know that our chip was not commercially ready (Brain staff told that the chip wasn't robust enough) no market-ready products were produced and sold, hence two licenses that only paid two ironically lumpy sums.

We shouldn't expect revenue deriving from these two licenses. Sure we can win all the awards we want to and have the best universities and start ups as partners but as long as we don't make significant revenue whilst keeping expenses as low as possible it really doesn't mean a lot because we don't have the financials to support this company.