Wlad is brutally knocked out Vitali is an awkward one. Either the ref stops it in the middle rounds with Vitali's face looking like a bloody piece of meat, or Foreman gasses late and gets stopped. Vitali, for all intensive purposes, is not on Foreman's level, but is a bad matchup for him.
Both brothers beat him easily. Wlad knocks him out after keeping him at range and jabbing his face off all night. Vitali wears him out and knocks him out late. Nothing he can do against bigger stronger fighters who he can't bully like he's used to doing.
Either fight could go either way. Could be Wlad manages to jab and smother his way to a decision after overcoming some scary early moments. Could be that Foreman hurts him early and doesn't let him recover. Could be that Vitali uses his size and length to outlast Foreman, could be he doesn't.