There is no gas benefit caching a global variable like, msg.sender, block.timestamp etc. Moreover, the cached timestamp is only used once in either the if block or the last line of return, which further defeat the purpose of variable caching.
https://github.com/GenerationSoftware/pt-v5-cgda-liquidator/blob/7f95bcacd4a566c2becb98d55c1886cadbaa8897/src/LiquidationPair.sol#L375-L383
