So I tested this today, and it "appears" that the DLC works for both games, because when you have your original 2020 DLC installed then install the same preserved collection DLC in TSW 2, they all stay in place, hence they don't disappear or delete like they used to, or the even game for that matter. But when you load up 2020 pretty much all the DLC isn't recognized anymore, only 2 for some reason, the CN route and WSR. All the others just weren't in the game anymore, and it actually went back to saying I had the founders addition. The only way I was able to fix it was deleting all the PresCo content from TSW2 and DLC from 2020, then reinstalling the 2020 content. So yes I can confidently say, this problem has not been resolved.