I have no knowledge specific to this company, but I did check and it looks like they last raised a “series e” round which suggests at least 6 rounds of funding.

It’s grown pretty normal over the last ~10 years for investors to enable founders to sell some of their own shares, thus taking some of the round directly into their pockets. Normally called “taking money off the table” the idea behind it is that a founder with a successful company should be able to participate in the success without forcing an early exit that might not be best for the investors.

Not saying that’s what happened here but occasionally you can get money off the table by selling some of your equity during a funding round. Afaik that’s how Hopin and WeWork ceos got hundreds of millions despite their companies going to zero basically

It is possible to sell some of your equity during funding rounds, they may have cashed out a significant amount along the way.