G.B.
You're going about this all wrong mamakitty. It's not this hard. There was no reason to do all the work you did twice. Sorry.
I suggest you do this. It works.
I check the kids every week so I have it down to a science.
I wash the kiddo's hair normally. I comb it out with a regular comb or brush with conditioner in the shower. I rinse it well. It should have very few tangles and be drippy wet.
Have her lay across a table, your lap, etc...on a towel. Take a rat tail comb, a fork tine, a pair of tweezers, etc...to part off the hair in small parts. Take a section that is about 1/4 inch deep and about 3/4 of an inch wide. Examine this section carefully. Look at the roots, the middle section, and the ends. If you see any live bugs pull them out with tweezers or your nails. Then drop them into a cup or bowl of water. They drown. The water makes them sluggish and as long as the hair is wet they will be extremely slow. Keep the hair wet. If you see a white nit that means it's empty. There is nothing in it anymore and it's basically dead. If it has a dark center it has a baby in it, these must be pulled out or that individual hair has to be clipped off. If there are many nits in the hair then don't clip it, pull the nit out with your nails.
Do this every day for a week or until you don't see anything in their hair at all. Then do this every week, I do it on Saturday morning after the kiddo gets out of the shower. I do sometimes not do it every week but only if it's been an extremely long time since a break out at school.
Please don't use any more chemicals on your skin. It's a pesticide, poison, not healthy. IF you do decide to wash with a chemical then use Lice MD. It's not a pesticide.
Nits are the left over egg, it's empty. It signify's there are live bugs, if you've gone through and removed all of the bugs and tried to get all the nits out then she should be allowed back in.