Ear blockage - sinuses?

[BabyOrSanta]

Since everyone's so helpful on this board (and I like learning too much...) I have yet another minor ailment I'm hoping you can help with.

My mother had an ear infection that she didn't get antibiotics for for at least 3 months. 3 courses of antibiotics and antibiotic spray later, one ear is fine but the other is still "bunged up". The nurse has said the infection is gone but that the "bunged up-ness" is to do with her sinuses...

The rest of her sinus-system seems fine. Vicks is making her eyes water etc.
But the ear thing still isn't shifting and the Vicks isn't moving that far along the sinuses.
She also can't get the ear wet inside as then she loses her hearing.

Anything else she can try?

Otovent, it works wonders at equalising pressure so may be worth a try. It's essentially a balloon you blow up via a nosepiece and there are techniques on YouTube (I found it after desperately googling one night when I was sick of not being able to hear due to my own ENT issues)