Big firm. We should have been using an education-specific boutique for this specific thing, but this started happened when we were tiny and still figuring a lot.
I can attest to having a similar issue in a startup that got large, we used one of the big firms for 100% of the work and should have been doing 10% of it with a specialized firm. It's not really startup advice you get, but it can be very costly later. Glad you got it sorted out.
For what it’s worth, $75k and whatever time you spend on this doesn’t seem like a massive amount. I feel like you took a risk when you had many other things to do and the risk was calculated and overall worth it — even if you got unlucky.
It could be worse. I’ve never lost any sleep because of it. Regulators have the best of intentions in California so far as I can tell, so just a few hoops to jump through.