Fisk: Perhaps the acquisition of Curbside LLC was a miscalculation...
Well, as a gauntlet, it's pretty stacked, and as you mentioned, this estimate was based on fighting Spider-man. More recently,
that's kinda one-sided.
At the same time, this is a scenario, so there is a sliver of hope for the big man.
Sure, they could kill everyone inside...but there are optics to consider, and there may be some ways Kingpin can weasel out of this one. I don't think anyone, except maybe Peggy Carter, Daredevil, Jessica Jones and the other two Fisks, would be able to do much to pull the lever on tax law, but standard knowledge on Kingpin would still make him known as a very wealthy man.
Riki-Oh, for instance, coul be bailed from his prison sentence, and Norman Osbourn, ousted from his own board of directors, would be grateful for some funding, maybe they could be bought. Possibly Blade and Selene could do with more silver or UV bullets or something, these niche weapons aren't cheap.
And really, would Peggy start swinging and cause an international incident based on hearsay alone? Captain Carter has an image and optics to consider...I think, never seen that show.
...granted, the sit and talk and offer bribes strategy likely won't work for the rest of them, many of whom will land a punch before Fisk can deliver an elevator pitch while also pleasing/saving the live of the members of the board who are very much in the wrong place at the wrong time.