I am sorry to say that I find it hard to understand your posts, even though I appreciate that you are embarrassed by going into intimate details. I think you are very brave to ask these questions in order to provide the best personal care for your wife. If it is too embarrassing to use a word, there are usually understandable alternatives. I suggest yeast infection, or Candida, rather than 'garden bird'.
I think you are describing a problem whereby your wife is experiencing a sticky discharge caused by the thrush, which then makes her incontinence pants stick to her body hair? Ouch!
And/or, due to vaginal prolapse, some of her naturally lubricated internal mucous membrane is protruding and making contact with the pad?
See, I am just a woman not a lady, and can therefore describe in graphic terms that garden implement upon which a different garden bird is known to perch. Call a spade a spade, in other words.
I don't think it is a good idea to use sticky barrier creams such as Vaseline, Sudocrem etc. because they provide a growing medium for bugs. When a person is using incontinence products, air does not get to their intimate areas the way it would if they were only wearing cotton underwear. With these heavy creams, germs get trapped against the skin so that UTIs and skin infections are actually more like to happen.
I recommend regular cleansing of the perineum and vulva (technical names for downstairs outside lady parts). You can get unperfumed non-oily baby wipes, or gauze squares which can be wetted with warm water. After cleansing with a wet wipe, dab the area gently with a dry gauze pad. Cleansing away the discharge after every toilet visit or pad change will make her more comfortable and less likely to experience pad cling.
Your GP surgery should be able to refer you to the practice nurse, or the incontinence nurse, who can advise further and may be able to prescribe things such as gauze pads and disposable gloves without you having to pay for them.
Did the consultant discuss the possibility of using a ring pessary for prolapse? This is a rubber or silicone ring that is inserted by a doctor or nurse, and stays in place for 4-6 months. It does the job that muscles used to do and keeps various female lower organs in their right positions, and reduces pressure on the bladder. This might not be appropriate to your wife's situation, but if it hasn't been mentioned to you then it is worth asking about it.