Another colleague showed me this… it is unfortunate, because this story is all too common.
However there are options to explore- OIC being one, especially if all of his wealth was from crypto. He could also section 1031 (I do not recommend that) and push his gain to 2018 to offset his losses. I have heard of many people doing that.
That said- he needs to see a crypto tax accountant or even an attorney and discuss his options. He isn’t screwed until the IRS demands money and even then, there are still options.