Puzzle and Citadel.one are building different products, I believe. If I understand that correctly, Puzzle is building an interface for wallets to be used with Secret Bridge and sSCRT Converter (though we already have those interfaces in Keplr and Secret Bridge website). It’s a product solely designed for Secret Network.
Citadel.one is a cross chain wallet. This means we are not only going to integrate the bridge, but are planning to integrate all supported ERC-20 tokens + BAND + OCEAN to our wallet, too. This will be a wallet, for example for BAND or AAVE with staking and sending/receiving functionality for them, which means there will be basic BAND and AAVE users that might come for staking or just for a wallet to Citadel, but later will find out that they can also wrap their assets into secret and enjoy this feature as well. So this will be an all-in-one product without needing to connect anything else. I don’t see Aave users coming to Puzzle to stake their AAVE
Those are different experiences, thus two different products, so I don’t see this as a double spending.