Can you find out who was deleted?

You can make your guess and it is very likely right. Symmetrick.

Can a merit source re-start Ratimov merit threads.

Today I am leaving the MixTum.io campaign, thank you for the opportunity to represent this service.

Symmetrick wants to take a break or leave the forum so it makes sense if he sent a request to be removed as a merit source.

Quote

Most 200 Merit sources are for local boards only.

I am not sure about it.