Upvote:4
Legally, the case is clear, at least as far as the compensation goes. It's rather a question of enforcement.
AirEuropa is an EU carrier, flying into an EU airport, so the EU passeger rights regulation (261/2004) does apply.
As you were denied boarding, you have a right to the standard compensation of 600 EUR, per Article 4 und 7 (the Internet says the distance seems to be just above 3500km, but I didn't check the distance between the airports specifically).
This compensation is for your inconvenience, not for expenses. You can get this on top of everything else.
Expenses are covered in the "Right to care" (Article 9): This includes meals, refreshments and accomodation if necessary and is in addition to the compensation.
I'd argue that this includes your hotel stay, even though the airline may argue that your travel had already ended at this point.
The fact that "all other passengers checked in online" has no meaning at all. You had a valid reserevation and presented yourself early enough. It does not matter that you are not a EU citizen, and you cannot legally give up those rights.
Almost everything you said about the interaction with the airline sound fishy. Normally you would have at least been allowed to the gate on a standby basis, even if they couldn't check you in, just in case some other passengers didn't show.
The could also have called for volunteers at the gate. Good airlines often do, as this makes everyone happy: The volunteer also gets the compensation, and usually someone is happy to take the money and the next flight.
The reason not to make the call would be that if they don't you may not claim the compensation, and they save the money. Together with the absurd mail that they sent, I'd guess that this is their main interest.
While I cannot say for sure, you should labor under the assumption that everyone you interact with is instructed and paid to try and make your claim go away.
Your task is to make the airline understand that the claim will not go away, not matter what they do, and that it is in their own best interest to pay up.
I'd first write to them that you specifically claim compensation and reimburs*m*nt for your costs under EU regulation 261/2004, clearly state that it applies in this case.
Present all the receipts and information that may be necessary, but keep copies. Set a (reasonable, not next week) date at which you expect their response and reaction. Tell them that even if they cannot process the reimburs*m*nt right away, they should send the compensation right away, as there is no doubt that it applies here.
Say that if you don't hear by them until then, you will take legal action and hold them liable for all expenses that result from their inaction.
If they do not react by that date, give them a "last chance" to react, and set a new date.
If they still stalling, you can either hire a legal counsel (which you may have to pay yourself); or give the case to one of the "EU flight rights portals". Those will take legal action on your behalf; you only pay a percentage of the compensation if you are successful. I'd say that for the portals it shouldn't make a difference if you're from outside the EU.
If they pay only the compensation and refuse the reimburs*m*nts, it is your call if you want to fight or let it slip. This is a bit less clear-cut than the compensation case; and if you don't find a flight-rights-portal that takes it on you may want to compare the risk of litigation against the cost of the night in the hotel.