Will Jeremy, Ken, Alexander be at the final show? two of them got ejected and one walked out so obviously their circumstances may not allow them there

I think Alexander will be there, but not the other two

There is no way they will allow Jeremy back.

Very much doubt it. Besides, why would they want to after the way they have been treated.

The 1984 origins of the show become deadly apparent when it comes to treatment of ejected housemates.

They become strictly Forbidden and must never be spoken of ever again. Ever.