It is rare in the startup world, and even more so among the less experienced people who often lose perspective at the sight of money.
The ideal solution is to engage in office politics, but there's not much time, and we techies generally suck at it. It won't be playing on your home turf.
> I plan to spend my all remaining days until the next meeting to prepare the hugest report ever written
I doubt that will get their attention.
It has to be:
1. Short
2. Convincing (read scary)
Focus on two messages only:
* you will go to jail *
* you are killing the future of the company when it's generally well-off *
Create examples. Cite business people (NOT techies!) calling it a fraud. While I said "short", the list of examples should be as long as possible.
Finally, ask the question: how many companies that ICO'd got acquired?
The answer is none. There are just speculations (https://www.coindesk.com/ico-ma-token-exits-get-messy/ and https://www.reddit.com/r/ethtrader/comments/6kfumc/what_happ...).
As the lawyers in the large organisations are paranoid, they will simply stay clear of it until someone else did it.