They announced Nothing but Thieves last week who also is playing Rock Werchter next week. If another Werchter act is coming, why are they announced seperately? Seems unlikely to me.
Fontaines DC is occupied during PKP.
Idles are playing AB after the weekend of PKP.
Sam Fender returns in August to Europe, but he is only playing 3 shows and is available during PKP, he would be great.
Fever 333 also looks occupied.
Maybe it will be smelly Maneskin???