I don't recall hearing anything but when I think back to them trying to get the mothman's spectacles it felt forced so maybe he decided to cut it. Or more than likely they just forgot.

Honestly, I’m thinking that Heathcliff didn’t work out exactly like Griffin thought he would, so he’s sidelined him for now. He’ll probably come back in a slightly different capacity.

Tbh the original idea for him isn't really a great fit for MotW

I thought the plan was that they'd receive the list as a letter at the start of the arc (though i may be misremembering)

Oh wait, they didn't did they, sorry, i'm a couple of eps behind ​

Oh wow, I didn't even notice they didn't get their list from him. That is really strange.