I do not know more about this case than any random reader of this thread.  However, the transition from incompetence to criminality seems to be common in similar situations.

When debts pile up and plans fail, a manager often chooses to risk some irregular workarounds (like mislabeling losses as long-term investments, using funds that he should not use, etc.) rather than admitting his incompetence (and perhaps losing his job).  When those workarounds too fail, he would be forced into even bigger violations of the rules to "fix" them.  At some point he recognizes that he has become a criminal, and then he will start planning and acting like one.  The CEOs of Enron, Worldcom, and even Madoff seem to have slipped down this path.

Another way a manager may slip into criminality is by paying himself and/or friends an exaggerated salary at a time when the company has more debts than capital.  That may seem a negligible risk at the time, but if the company goes bankrupt such generosity will be noted and it may get him charged with fraudulent management.

About those clients who bought bitcoins from Danny that were never delivered, for example: it may be (just an hypothesis) that Danny used that money to pay urgent debts, hoping that he would soon get some revenue somehow that would allow him to buy the bitcoins and honor the deal.  Or perhaps the deals were struck in September, he did not buy the coins immediately, and then found he could not do it after the price increased 5--10 times.