Norwegian already knew the Irish Judgement would be recognised in Norway, it is possible the same case exists for Spain,
If they hold "assets" in Spain in the form of shares in the subsidiary company, it could possibly be looked at, although the process there tends to heavily favour the creditors and the success rate of "restructuring" is typically less than 10%
They already converted "crew service debts" to equity, quite what happens after the ERTE scheme ends 31st Jan is anyones guess, perhaps employees can move to Fogasa.
Spain is an important market for them, if they can keep this operation and the Norway home base, dump LH they may well survive.