US Green Card holder (Russian citizen): Passport stolen in Spain - How to return...

I am a US Permanent Resident (Green Card holder) and a Russian citizen. I recently participated in a chess tournament in Spain (Benasque). After the event, my passport and a significant amount of money were stolen from my hotel room.

My main concern right now is how to return to the United States from Spain with only my Green Card. Returning to Russia to get a new passport is not an option for me, as I have work responsibilities and need to be back in the US as soon as possible. I have:

• A valid US Green Card
• A police report (denuncia) from the Guardia Civil in Benasque

Questions:

Is it possible for an airline to board me on a flight from Spain to the US with only a Green Card and the police report?

Can I apply for a boarding foil (Form I-131A / carrier documentation) at the US Embassy or Consulate in Spain (Madrid or Barcelona) in this situation?

What documents would I need to provide to the US authorities?

Has anyone been in a similar situation (lost/stolen foreign passport abroad while holding a US Green Card) and successfully returned to the US without first replacing the passport in their home country?

Any recommendations on who to contact at the US Consulate in Barcelona or the US Embassy in Madrid for urgent assistance?

Any practical advice or contacts would be greatly appreciated. This is quite urgent.

Is it possible for an airline to board me on a flight from Spain to the US with only a Green Card and the police report?

Yes. The US does not require permanent residents to have a passport to enter the United States, and TIMATIC, the system that airlines use for document checking, reflects this.

Can I apply for a boarding foil (Form I-131A / carrier documentation) at the US Embassy or Consulate in Spain (Madrid or Barcelona) in this situation?

Possibly, but you don't need one.

What documents would I need to provide to the US authorities?

Only your green card (unless you've been out of the US for longer than a year).

Has anyone been in a similar situation (lost/stolen foreign passport abroad while holding a US Green Card) and successfully returned to the US without first replacing the passport in their home country?

Probably.

Any recommendations on who to contact at the US Consulate in Barcelona or the US Embassy in Madrid for urgent assistance?

Unless you've lost your green card, which it seems you have not, there should be no need.

Your bigger problem will be providing the necessary documents to Schengen authorities at the exit check. The police report may be sufficient, but it may not be.