Considering small co‑investment in private employer vs staying fully indexed — how would other Bogleheads think through it?

Life long buy and hold index investor, trying to evaluate how I should think about an opportunity my company is giving me to co-invest.

Opportunity:

• Employer is offering a limited group of mid to upper management employees the chance to buy equity in the privately held company (I gather others in the comapny have been given this opportunity previously). I have a fairly high degree of trust in our current executive team and genuinely think this is a goodwill gesture after a string of acquisitions rather than a simple cash grab.
• Minimum investment ~$50k (≈3% of my invested net worth and that is likely the most I'd consider)
• Equity is true common equity alongside institutional owners (PE sponsor)
• Being offered at same price as large funding round late last year. Company's internal evaluation is now supposedly 20% higher ... though that's obviously just the company's guess.
• Company has meaningful debt it's recently taken on as part of acquisitions.
• Planned exit is IPO in ~3–6 years, but no guarantee and PE sale possible.
• No dividends expected prior to exit
• Shares are illiquid and cannot be sold unless there is an exit
• There is a contractual buyback right if an employee terminated for cause, but company counsel indicates they’ve at least never exercised this historically
• If exit goes well, modeled upside could be ~2x over several years (we're not an explosive growth industry, but I do feel we're currently very well managed with above average internal processes and development efforts). Downside could obviously include partial or full loss of capital, and might coincide with job loss.

Question: If I think of this as replacing 3% of my investments that would otherwise stay in my 80/20 portfolio, how would you evaluate the risk?

I fully understand that “stay the course” and simplicity are core principles — specifically looking for feedback on whether this violates those principles or can coexist with them if sized conservatively ... potentially even providing a bit more diversification.

My gut feeling is that I'd rather not be even more leveraged in my own company than I currently am. But also feel this is genuinely being offered as a goodwill gesture, which has me slightly reconsidering. So curious how other like-minded and fairly conservative investors would approach it.