I know you’re probably loathe to try too many things at once because it will be difficult to know what is really working. But with Snowie, who used to be incredibly itchy, it seems that removing salmon oil from his diet made a big difference. I can’t remember if Squidge gets that as a supplement? Also, his itching has reduced since getting turmeric paste. No idea if causal or not.
I also think that these English-bred dogs in hot dusty climates are just not suited to the climate—it makes them hot and they get heat rashes. Snowie’s father is from the UK and his coat is very thick. As soon as the cold winter weather hits, he’s far more comfortable and not itchy.
And yes, scratching and licking all night is really bad for everyone! You have my commiserations.