There are many instances of community takeovers of a coin. The main thing is to get the majority of the network to move to the community version of the wallet. This will first require various things to be done in the code before the community release to ensure that the new team can manage the sporks, possibly freeze/block/take-over the old developer funds, and obviously fix any major bugs, before deciding a new roadmap.
I don't think we have a community member able and willing to do this. Especially if listings are lost and the old developer is hiding.
RIP Masternodecon.