Basically he is telling MC not to trust him (ML) or the company? cuz the company is MC's original body's family Potatowo
Honestly don't not know, maybe not not to trust him but he's probably finding more and more hints that it's Hajin so I'd say yea about the latter part. He also doesn't seem to like Hajin's complete calmness towards life threatening situations.
Remind me who was Taekang?