You actually only need to tell him about another way of investment. But you never advice him or even force him to invest in Bitcoin. Let him decide himself whether he wants to invest or not. It is not easy to handle the financial of a company. We can't compare MicroStrategy and his company. It is probably too much different.
If you advice him, he has the right to blame you when he fails in Bitcoin investment. But if you only tell him a successful company in Bitcoin investment without giving any advice, you have no responsibility even if he fails in the future. TBH, I won't advice him to invest if I were you. I prefer to tell him about some successful companies in Bitcoin industry.
You can always tell your friend how profitable bitcoin investment is, but you can't lead him on his decision where to invest or if he's really interested to invest those money sleeping in the bank.