JET doesn't exist in the blockchain. It's an in-house coin. I don't see a point in this. You said we can print more JET. There's nothing like printing here since it doesn't exist in the blockchain. We just assign the value but we are liable to give you USD when you want to exchange.
Sure, you are liable, just like Tether USDT is liable to provide if you redeem the tokens. However it's a complex procedure involving huge fees with huge minimum deposit amount. So there are only few holders who would even do that. And without an audit you could have more JET than USD, that would only show if more people were exchanging to it then you have a budget for.
And you didn't answer to queston that was:
Why does it exist? And while i am on it, can you also answer to why not call it USD if value is pegged to USD? It's basically USD anyway.
I couldn't find even mention about JET from your FAQ, Blog, ToS, or help center. Not about JET or rules to redeem or exchange it. Not a word, so can you see how suspicious this is?