This is a "not ready for prime time" experiment at this time in the US. Maybe you can talk to your Mom's pulmonologist about finding a clinical trial.
There are a whole lot of reasons not to try this without medical guidance, not the least of which is the need to get medical grade honey from a reliable source. The next would be the danger of introducing a foreign substance to already extremely challenged lungs...can you bring it up to her pulmonologist?
Sue