On p.384 of the EP core rulebook, it states that rez points are awarded at the end of every story arc, at the break in the action between one adventure and the next.
With that in mind it's more important what your character did during the course of the story arc than how different forks may have helped him accomplish those feats. So for example, if sending an alpha fork to investigate the abandoned space station helped the character accomplish his objective, the merged character gets a rez point. Basically whatever happened to the alpha fork while it was off doing its thing doesn't matter. What matters is what the character did, whether he had to fork and merge to get the job done or not.