Look at this Rag:
I mean come on is that written purposely
It looks like you're asking whether this fighting style was deliberately written by someone, which seems like a silly and obvious thing to ask; of course it was deliberately written. It wasn't thrown together by cosmic space dust, after all.
But... that isn't what you asked or said there, is it? I just ignored the context of the words that came after what you said, and misconstrued your meaning. Was that your fault for not speaking clearly, or mine for ignoring the rest of what you said and not taking in the context? It was the latter, clearly. The same is true of your complaint:
The phrase in question is not: "for an attack that you make"
The phrase is: "The damage die for an attack that you make with a two-handed weapon"
Read in full without omitting part of the phrase, it's very clear that we're talking about the damage die here, and not the attack roll - they're separate things, and it's very obvious, painfully so, that it is the damage die that we are talking about. The context of that damage die, then is the damage die that we roll when we attack with a two-handed weapon.
The original text read like this:
"When you roll a 1 or 2 on a damage die for an attack you make with a melee weapon that you are wielding with two hands, you can reroll the die and must use the new roll, even if the new roll is a 1 or a 2. The weapon must have the two-handed or versatile property for you to gain this benefit."
Beyond that, "making an attack" is a thing that has a specific meaning - and that must be what you have done to reach the damage rolling step. If, for example, you dropped your sword off a balcony to spike someone in the skull when they walked underneath, you might roll damage die, and you might even roll the damage die for the weapon, but you have not "made an attack", and so GWF would not apply.
So... theoretical question: how would you do this, Rag?
How would you word this fighting style, so that it does everything it's supposed to, and doesn't end up doing or allowing things it's not meant to, without using the word 'attack'?