That does not really look so infeasible. But of course they would rely
on massive support from other countries, for which France is the first candidate.
It is then highly probable that these kingdoms end up under decisive French
influence.
And btw, I do not believe that several neighboring states would have the
chance to expand at the expense of the Arabs at the same time.
I rather think one of them could gain a remarkable success, while the others
staying as marginal as they were before, or even wither as small items
between France and "Greater Iberia".
But wouldn't the loss of the Iberian penisula question the stability of Arab rule
everywhere, or at least in Northern Africa well up to Egypt?