you did it early, for second time infecters, nix might be too weak.

For thickened skins, you can make sulfur cream your self: buy sulfur powder, and zinc oxidide cream 20%, calculate how much zinc oxide in it, and add the same amount of sulfur, first mix sulfur with some venigar if your skin is not dry, if it's too dry, mix with a bit coconut oil, now you have your own sulfur cream.sulfur dries the skin terribly, but with venigar or oil, you'll feel much better.
day and night, twice daily.wash off with venigar, then apply another, or shower off,anf venigar yourself before putting on again, or bath off with Epsom Salt and bit venigar , then apply again on.
In china, it's required not to wash in 5 days, just leave them on, and re-apply again and again.
In case your method does not work for you the next time, keep this in your note.
Epsom Salt can also make a 33% water , add a bit water, just put on the skin a lot, often, when ever you itch. but liquid will not help for the nioght, for the night, something thick and stick is definitely needed if mite population is big.
For whole body scabies, or more generation scabies, it is not as easy as your method, I have tried permethrine 5 days in a row, worked the first time, not working the second time any more. I think your dog shampoo might be strong enough. have not tried.
neem oil+turmeric works, it's a paste, work good for night. it's not that itch killing, adding mint, camphor, or essential oil will help ease the itch.
If one suffer too much, eat antihistamine. But never forget to do the same course. Tweet