I'm probably going to jinx myself since I haven't started the Cloning Around challenge.
During the Collecting Challenge, my two sims each spent a few days in the Scientist career (Level 1) and neither had any trouble receiving both a crystal and a metal from every co-worker they asked.
They stopped hitting up their co-workers, however, because I noticed that they were only receiving the cheaper stuff whereas my collections were missing the rarer crystals and metals.