We would say “jiggerche”/”jigger” for cooked liver – pronounced ji-ger.  But I must admit, our dialect is pretty archaic. Its survived for centuries of Hellenization and Ottoman era, and is largely a spoken language with little written influences.  I would say that the slavs from the region around Florina and Bitola would be descendants of the Tsamuil’s era given its proximity to Prespa.  I know that the villages around this region have been inhabited since the 15th Century at least (which is still well after Tsamuil’s era), but there is no written evidence of the inhabitants of the region through the ages.