who are the issuers of these futures

Hello @concepskip, in the section 4 of the whitepaper they explain the "main features and benefits" of this exchange.

In there, they mention how they are going to allow the exchange to have enough liquidity and they also mention the presence of the automated market makers. Which makes me think the exchange itself is going to be the one responsible for issueing the futures, although I would have to research a little bit more to confirm this.

are they cash settled or physical

In the whitepaper linked above, they mention and I quote "Tick values of futures contracts are denominated in DGTX tokens, meaning that all profits and losses are settled in DGTX tokens.".

I hope this reply can answer your questions.

Cheers.