I would say that you have not retired, even in the MMM sense, because your assets have no hope of supporting your annual expenses over the long term at this time. $300K in cash is losing value every day to inflation, and the shares in unlisted companies have no usable value other than the dividend.
Were I in your shoes, I would get that cash into the market, and fast. I would also aggressively work to reduce expenses and/or start accumulating-- for a person making $400K a year, you have comparatively little saved. If you really want to be retired in any sense, and your expenses continue to be $100K a year, then you need 2.5 Million in assets appreciating at %7 a year or greater, and some flexibility in the years where that doesn't occur.
Now, if you can look at your life and adjust your COL to ~30K a year, then you might be at the point of being able to retire. Remember, the "magic" multiplier is 25 x your annual expenses. So if your post-retirement expenses are 60K, you're almost halfway to that.