Did I ask too vague of a question?

Joined my coworkers casual commander play group which consists of him and his good friend.

It's down to his friend and I, it's my turn and it's down to the last couples turns. Hoping to get him close to 0 life before he potentially takes me out next turn. I take my main phase, and announce that I'm moving to combat. I look at his board and it's somewhat messy, so I ask him if he's open. He says yes, so I declare my attacking creature and he all of a sudden has a creature to block with.

I thought I was pretty clear by announcing combat phase, looking at his board and then looking at him and asking directly if "he's open" that I was referring to the state of all his creatures being tapped or not. Is this phrase not commonly used anymore to reference such thing? I called him out on it and he said, "yeah I'm open for business" and laughed.

I know I didn't ask directly, but he responded like he knew what I was referring to. Is it wrong to think he was being disingenuous with his response? He had some pretty inaccurate rulings on some mechanics and at one point tried to manipulate the text on a card to do something it can't do. He didn't seem like a very honest player.

Would this be lying about free information? Or is this a question of morals/good faith. (sorry for the long post)