Well he's as much a world champion as Nobuo Nashiro, Poonsawat Kratingdaenggym, Yuriorkis Gamboa, Paulus Moses and Vyacheslav Senchenko. In other words, no. It's bad enough having multiple champions in a weight division, but multiple champions per sanctioning body? It's ridiculous.
It's worse than an interim champion though, because Ward has no obligation to face Sartison. Not because he's in the Super 6, because "Super Champions" don't have any mandatories. So they have effectively created 2 world titles.
The WBA are only supposed to make people super champs if a WBA champ wins or holds another bodies title at the same time. Awful idea, that ruins the titles credability. In Kesslers case he was WBA champ, the WBA made him super champ cause the belt would be tied up in the super 6 competition even though he wasnt holding another title at that time. So this to me now makes Ward WBA champ. In answer to your question with Sartison id say no, but dont blame him contesting for the belt to get some recognition, he could even be defending next against undefeated Mendy, but I wonder what would happen to the title if Sartison and Bute had a unification match, the winner would be a genuine IBF champ holding a substitute WBA belt, so would they make 2 super champs and bring out a 3rd WBA title in the division? Awful mess