Dev is alive but not active
Of course dev is active, he is sending out withdrawals once a week. Hope that he is also developing the exchange, but I don't think so. It was a one man show and every one man show comes to an end!
Maybe development has no ability to continue to develop, and it has already made enough money. Now he process withdrawals once a week, may suddenly give up this project later.
I am wondering how dev made enough money? By selling at 20 cents? If he really wanted to dump them he could have sold at $2 and scam projects do not put much effort where they are eventually going to scam. If we look at the airdrop distribution and bounties then we can see that dev had indeed put great amount of effort.