Do you plan to keep treating for a while to make sure you get them all?
Walnut can actully increase growth of some parasites so that was a good call to find. Also, finding that 400 mg of Albendazole was correct for you. Much reading and I found that 400 was norm and depending on weight 800 for certain Tapeworm type infections and some flukes have also been treated with higher doses.
I read once that the zapper increases growth of Tapeworms and should not be used, another good call. Unfortunately you found out the expensive way.
I sure hope you keep up with some maintenance to make sure something doesn't grow back!