As I understand it, PeachBitcoin is a centralized coordinator of all swaps, controlling one of the signatures in the multisig of each deal. If it shuts down and bitcoins get stuck in escrow for a swap, it would be difficult to retrieve them, and without the active cooperation of the other party to the exchange, completely impossible.
I never said PeachBitcoin app was decentralized but I never heard any cases of people losing their money or coins getting stuck, and rating on kycnot.me is also good.
There is also reputation system on this app so it's a good idea to avoid trading with someone who has low or no reputation.
So this is NOT a DEX, but decent option for trading BTC to cash and vice versa.