On a point of order, yes, there are rules, as you so correctly stated. You as chair make the decision to enforce a rule, to interpret a rule, and decide whether or not it is applicable.
You have made a decision that, one, there is a rule, and two, it is applicable to Mr. Lukiwski's motion. Therefore, there is a member here who has challenged your decision that the so-called rule is applicable. That means there's no debate, there's a vote.