To be eligible for winning a rule a player must have at least one card in his pallet to which the rule can apply. Because a player may not play a card to the canvas if he would not be winning, he may not play green without an even card or violet without a card below 4, so a zero card tie can't happen with either of those rules.
There's nothing in the rules that says you have to have at least 1 card to meet the rule.
My take is that if you all 'tie' with zero cards that meet the rule, then you default to the Red rule. This would be an interesting play if you were losing on the current rule but could win with the Red rule but didn't have a Red card OR didn't want to play it as the rule for some reason - you could force it to be a 'tie' and then be winning by the Red rule....
Nevermind - you're right - the rules say you must have one card to be winning with Green and Violet rules...