I don't understand what you are basing these wild claims on.
Pickering will be off come what may (he only signed for Scunny because he priced himself out of a place in Poland)
Zack Cook will drop the Championship as part of his natural progression like dozens of other riders have done before ( e.g. Ben Cook, Tom Brennan)
Dan Thompson has a real decision to make: does he want to watch speedway in Lodz or ride speedway in Edinburgh? If the latter as Lisa suggests then we haven't lost him.
Masters/Lawson/Flint/Jeppesen/Wright etc ride in tier 3 so are not affected
I hardly think King, Batchelor and Harris et al are going to resume their Polish careers
Nor do I see the likes of Etheridge, Edwards or Sedgmen attracting Ekstraliga interest.
So the sum total of riders at risk appears to be:
Anders Rowe (and possibly Dan Thompson).
Isn't the bigger risk that riders may drop the Premiership to protect Swedish or Danish contracts?