Few points here:
1. Did you request records of how funds were used, who got what, and can produce them for us to all view? Do you know the money was already spent or is it being kept in treasury? I believe they're supposed to be publicly available.
2. Is there a distinction between paying someone to do a job, and they use that that money to travel for relevant purposes, VS. paying for their travel? If someone is paid through a grant for work they did, is that not their money to do with as they please?
3. The point of the projects is to generate reference designs so that others can produce products based on them, not so they can directly produce a specific product. The idea being that it becomes infrastructure in the same way linux is. That shouldn't be rushed. You should get it right the first time.
4. You say none of it is done, but I've connected to Hydrapool, I've seen Mujina go (it's even been forked for BCB), I've seen the EmberOne and Libreboard in person, these all do exist and they are working as prototypes. Are you keeping up in the telegram group with what's happening?
5. These guys are definitely not getting rich from doing this. They're skilled engineers that could certainly be making a hell of a lot more money with a regular job.
6. I don't know anything about running a 501c3, but it's probably pretty distinctly different than a business with its own set of challenges. We can investigate and ask question without casting aspersions though, accountability for accusations is just as important.