a quick searched found these 2 aspect of his finality, I don't know enough to say, but it is interesting

W.D Gann died broke?
Some time ago Soultrader commented on Gann: "Gann died broke"... end of story, right? Well, if everything would be that simple in this world. Personally I can not find a proof for that statement and oposite either. But on the other hand notice some facts:
1). "By 1936 the lowest tax rate had reached 4 percent and the top rate was up to 79 percent."
2). Gann bought a plane.
3). Gann was hiring 25 (some say 35) people constantly in his wall street office.
Now, taxes and his plane is very interesting. Some say that: "Gann used planes to inspect crops, however this is highly unlikely as he knew in advance what the market was doing". Dont you think it would be strange for him to inspect crops? Now checkt this theory out: ""It was possible that the planes were a tax deduction and he flew the money he made to a South American bank account." Is this a proof that he wasnt broke? No, its not. Its just a theory. The same theory as the one he died broke.

There is, however, much speculation that when Gann died he
was effectively broke, leaving only about $100,000 in his estate.
The estate was divided up between relations and siblings who
each received very little. It is possible that this was a final ‘pay-
back’ for Gann’s family’s frequent requests for money, and their
failure to support his work. His own son, John Gann, did not
believe in Gann’s work, and made no secret of it. According to
Gann’s third wife Londi Gann, who died around 12 years ago, John
would make paper planes in jest in his father’s office as an adult.
The two seem not to have respected each other.
It is also believed that Gann gave a million dollars to the Masonic
Lodge, so perhaps more of his funds went there in the end. I
believe it is likely that Gann left his money in Cuba, a tax haven
in the 1940s and 50s. In his ephemeris of March and April 1949,
Gann noted ‘won the lottery’. From the number of wins recorded
in his ephemeris, it appears that Gann may have been playing the
roulette wheel, which is based on astrology. We know from Gann’s
wife that Gann also made a lot of money at the races