Another suggestion?
I suppose you could try a hydrocortisone spray instead of using the cream. Of course, that is assuming that it is available there. The hydrocortisone "stuff" is all the same percentages whether for humans or pets. I used to use it occasionally on my lil' ol' lady Muffin.
Other than that I would suggest trying different anti-itch shampoos until I found one that worked. It's pitiful that neither of you can get any relief!