If the decentralized assets are purchased directly via the DEX, then it is the duty of care of each individual to carefully check the current price displayed there. This is because it comes about completely decentralized through supply and demand. Price oracles play no role here; they are only used during the minting process of loan tokens.
So when you create a new dTSLA token using your Vault, you always do so at the price set by the price oracles, which take into account several variable factors and apply them to the displayed price. The price of assets on the DEX is independent of this and comes solely from supply and demand.
Since you can't create assets on Bake, you have to rely on the price of the DEX from the DeFiChain.