Has he done it yet, or what has he been up to?
On March 25th of 2018, Mike Hughes did indeed complete his rocket launch, and survived. Quite a feat for a homemade rocket done on a shoestring. He flew to an altitude of 570 meters (1875 ft) over the Mojave desert, and his rocket safely parachuted back to Earth. Hughes says he never intended to go high enough to positively discern if the earth is flat, or not. Have to keep the delusion going would be one interpretation. On a less cynical note, it’s not easy to reach 35k feet of altitude in a homemade rocket, which is what it takes to see the curvature of the Earth. Of course one only has to take a commercial flight to see the curve.

He died of unattended physics caused by an engineering deficiency two years ago.
His rocket, which I think we all know was a rickety piece of shit with a steam motor (i.e., short burn, high acceleration, as opposed to a steadier burn with a slower build-up), fired its parachute on launch, and the launch forced ripped it off. The high g forces led to a G-LOC (G focre-induced loss of consciousness), and he slammed into the ground having maxed out at about 5,000 feet.
Mike Hughes went up about as high as he planned to (give or take a bit). What he was actually doing was testing his technology, particularly his engine.
Now he had to get some funding to get it all together, but mainstream funding is a bit leery of efforts like his, being amateur and trying novel things, so that wasn’t a good avenue. Top Gear had already done something similar, so there weren’t a lot of options left.
Then Mike showed a true streak of genius. He needed people who would fund him, regardless of the apparent merits of his technology. That meant people who weren’t skeptical, but were seriously gullible. Where to find them? Who are the most gullible people out there at the moment? Flattards seem to be right up there. So he conned them into supporting his test flight by feeding them (and the wider world) a whole lot of claptrap. They fell for it, Mike got his funding for the test, and he’s letting it slip that his flat-Earth support was really only for the cash.
Mike didn’t establish anything about the flat Earth. As he said, he never tried to. He just did two things, and appears to have done them well. First, he tested his technology and within his parameters is appears to have worked well. Second, he tested the adage that a fool and his money are soon parted, and that also seems to have been a resounding success.
Mike Hughes may be ‘Mad,’ he may even be a ‘crackpot’ to some. But I think he’s an individual (or possibly even an eccentric, in the best sense of the word) who wants to try his ideas out his way, and he seems to be pretty smart in how he goes about it. I reckon he’s great!