I'd advise caution with investments you can't exit easily. Doubly so for those that require agreement between family members... or other families.
Your fear of the 2008 crisis happening again exactly as you invest is irrational. Unfortunately vivid events really stick in your brain, despite the odds being very distant. You should run simulations and look at historical data until you're convinced how rare that one -50% event really is. Other crashes were much milder.
If this money is "enough" for you, there's a second consideration: why are you trying to grow it? You should aim to preserve it. That means a significant allocation to bonds. When a market loss of -25% occurs, if you are 50/50 stocks/bonds, bonds historically won't fall sharply like stocks. So the loss might be closer to half that, or even less if bonds move opposite stocks. And after that kind of drop, you can rebalance: you sell bonds and buy stocks, then wait. You're looking at market crashes but ignoring the recovery that typically follows a crash.
I'd suggest picking an allocation other than 100% stocks/risky assets. Treat this money as providing a possible retirement whenever you want it, and protect it using safer assets like bonds or bond funds. Also with $2MM in assets, you probably want tax-exempt bonds.