Please could elaborate on liquidation price oracle you are using in lending. Do you you use chainlink ? Dex price ?
Now we only use TOMO/USDT on DEX to calculate liquidation. About the TOMO borrowing, for example you borrow TOMO with collateral is ETH then price of ETH/TOMO on TomoDEX will be used and it happen the same with BTC/TOMO pair. Anyway personally I think oracle service from chainlink might be a good option here.