So so far we've had the former US Joint Chiefs of Staff Gen. Martin Dempsey say in 2014 that major Arab allies (Saudi & Qatar obviously) fund ISIS. A German minister accused Qatar of funding IS. Trump said Saudi funds IS. Which other major figure did I forget.
With all the other evidence I think it's hard to dispute that now but of course some will keep insisting on it. How can these terrorist regimes be forgiven for support to such a group? IS hitting the west finally woke them up and we see the results of the leaders they're getting in power now.