I don't know what you're babbling about. If you think that these teams are not tier 1 then you must either have a peanut inside your head or you just hit your head hard before writing this. These teams are tier 1, given the fact that these teams have the capability to beat teams from EMEA or NA. PRX was the team that almost beat SMB and NU almost beat Fnatic back in Iceland. If these teams aren't tier 1 then I don't know what is tier 1 in your definition.
If Heat has the ability to Jett diff Yay, who's arguably the best Jett in the world then I don't find why any of these Jetts can't diff ScreaM too. After all he got diffed by a tier 2 Jett and a tier 2 Killjoy.