I once was also faced with something absolutely unacceptable to which the hotel, nor the IHG standard support were willing to offer any resolution for.

It was taken up by "a senior case manager".

Conclusion was the same as above: ".. unfortunately, due to your specific concerns with the Hotel, IHG is unable to bring this matter to resolution for you. The Hotel must resolve this matter. Most of our Hotels are independently owned and operated, therefore, they must be the entity that resolve your concerns."

A pretty polite way to say fvck off, we dont care.