Ring of the Void and Same hand size

So, this came up in a game today, and when I was talking to my opponent about it, he said that a judge at our recent Kotei ruled that this is illegal. So I wanted to check the timing on this one:

Text Void • Unique After you resolve your fourth or later non-Kiho action from Strategies in one phase: You may put his card into play from your hand. Open: Bow this card or discard it from your hand: If any player has more cards in his hand than you do, or if you bowed this card, draw a card.

Let's say I have 7 cards in hand and so does my opponent. From what I know about timing, costs should trigger first. So you discard your Ring of the Void. Next is effects, If any player has more cards in his hand than you do then you draw the card. Since I discard Void as part of costs before effect text (and I now have 6 cards in hand), shouldn't Ring of the Void still draw you a card?

My thought process says yes because you discard first, then as part of effects you check handsizes. (Me) 6-7 (Them) I should be allowed to draw a card, yes?

Thanks.

You are right: mandatory costs are paid before effects are applied (see Abilities and actions), therefore if all players have the same number of cards in their respective hands, and you discard your Ring of the Void as a cost of its own action, then you have fewer cards in your hand than any other player so you draw a card.