The first thing I did was look at the population of Josvainiai. Very small so Wolfberg is more likely to be all one family.
Then I searched Wolfberg in Josvainiai. I see a Tsalel with a number of sons who have their own households.
I would build a family tree coming down from Tsalel and looking at the names his sons named their children. Leyba is one of the sons of Tsalel. I see Abram Itsko son of a Leyba as head of a household. And I notice right away that Abram Itsko has named his children names matching the given names that the sons of Tsalel named their sons: Gesel, Tsalel.
So that tells me that All these Volfbergs are in the same family and it's highly likely that Abram Itsik is the son of the Leyba who is the son of Tsalel. Leyba is the brother of Mordechai Rubin and Shlema. So I do believe that Abram Itsko is the son of Leyba, son of Tsalel.
As for Rivka Volfberg Keidanaski and Khiena Riva, I would NOT assume that Abram Itsko and Abram Yankel are the same man without further investigating. And in fact, the given names of the children of the Keidanski couple, do not at a glance to my eyes support her being the daughter of Abram Itsko son of Leyba son of Tsalel.
Also, Tsalel was NEVER known as Charles if he lived and died in the Kaunas Gubernia. I would edit his profile. Charles was the Anglicization that many of my Calko / Tsalko relatives took upon coming to America, which I assume is why someone has given his name as Charles. Did I miss something?
I have to do more looking into Rivka Keidanski but I'm not convinced she is the daughter of Abram Itsko.