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. This is to avoid putting you in a dangerous situation because if your friend follows your financial advice, and eventually fail in the long run, then you will be held responsible of his losses, simply because you were the one who introduced him to bitcoin. You can encourage him to research about bitcoin but you can never tell him to forcefully invest on it.
Probably the best is to just give the benefits and downsides of investing in Bitcoin. It's only an advice so it'll be up to them but sometimes, it can be really appealing, especially for first-timers thinking that it's going to be an easy investment. If you look back, people who made money from BTC and Crypto were those who had the capacity to hold on to their assets regardless of the market's extreme movements. Imagine investing a big amount of money that was handed over to you and then seeing your investment plunge deeply below its original value. Panic is sure to follow and losing money would not be far behind. I think its better to have them consider BTC as an option after they're aware of what they can lose.