To add to that, the validity of the votes are questionable in the first place: https://en.wikipedia.org/wiki/Catalan_independence_referendu...

> Due to the many irregularities and to the actions taken by the national police and civil guard, the international observers, invited by the Generalitat, declared that the referendum results could not be considered valid as the process failed to meet the minimum international standards for elections.

IMO the Catalan government just lost any legitimacy they might have hoped to have by declaring independence prematurely.