“Za Batorego na czele Żydów polskich wysuwa się rodzina Wall lub Katzenellenbogen z Brześcia nad Bugiem” – It says that during the rule of Polish king Batory Wall family becomes the head of Polish jews. (source)
But surname Wall also is mentioned as part of Oksza coat of arms.
From what I’ve read Czech prince appears only as a part of some familly legend of one of the families using this coat of arms. Wall seems to be just one of the many surnames related to Oksza. Also having such surname doesnt mean that one is descendant of family being part of Oksza coat. Wall is used by Germans, Brits and even jews. It doesnt have Slavonic source but it could of course be part of nobility in Czechia ,Poland or Hungary.