The descendants of Benjamin

In Numbers, chapter 26:38-41, there was a substantial difference between the list of the descendants of Benjamin in Genesis and here.  Here there are only 5 descendants, while in Genesis, there were 10 descendants.  Only 2 are the same Bela and Ashbel.  Bela was another name for the place called Zoar in Genesis.  In fact, today there are many places throughout the world named Bela.  There will be other people named Bela in other biblical tales.  Those missing from this list are Becher, Gera, Naaman, Ehi, Rosh, Muppim, Huppim, and Ard.  Becher is listed as a son of Ephraim, so that may be why he was not here.  In later books of the Bible, Gera is listed as a son of Benjamin, but not here.  Naaman and Ard are listed as the descendants of Bela, not of Benjamin as in Genesis.  The mention of Ehi and Muppim in Genesis are the only mentions of these two in the biblical works.  Rosh is some sort of kingdom in later works.  It is possible that Hupham is just another way of saying Huppim, since they are both listed only once here in Numbers and Genesis.  Both Ahiram and Shephupham are only listed here and in no other works.  Bela had his clan of the Belaites.  His two sons had their own clans.  Ard had his clan of the Ardites and Naaman had his clan of the Naamites.  Ashbel had his clan of the Ashbelites.  Ahiram had his clan of the Ahiramites.  Shephupham had his clan of the Shuphamites.  Hupham had his clan of the Huphamites.  These were the clans of Benjamin that increased by 10,200, 45,600 from 35,400, without any reason for this increase.  What do you know about Benjamin?