I still do not believe that this project was a scam.
Why?

1) There was no benefit for scammers.
2) The team did not behave like scammers. They kept their promises.
3) The project was too bad to be scam (bad website, draft whitepaper)
4) There is no evidence for scam.

So, there must be another reason why the Dev has been quiet for a while.

Four things can happen now:

1) The project is dead and remains dead.
2) The Dev comes back with a good excuse.
3) People around the Dev take over (as sometimes with other projects)
4) The community takes over (as sometimes with other projects)

I'm waiting. I do not have another option.