I see the child managed to stay 8 months. But it is not up to the child to decide where they live.
The mother changed her mind obviously. At 6 months, the father could have filed for custody in WA, but failed to do so and does not have the legal right of custody. The fact that the child is in school and has a job does not trump the mother's right to custody---and quite frankly, if I may be blunt about this matter, utter contempt for a court order is highly unlikely to result in the court siding with the offending party just because the actions comprising the contempt may work to the benefit of the child. The ends are not justified by the means.
What happened here is one or two steps removed from child stealing---perhaps the biggest difference being that in this case the child wanted to be stolen and perhaps initiated it. I don't see a court being all that sympathetic to the arguments of the father or child at this point. I am sorry, but the mother can and likely will receive the pick-up order in this contempt motion.
If the child returning to FL would place the child in imminent danger of physical harm, then you can ask the family law court in WA for an emergency order for temporary custody---while the allegations of physical danger will be set for a full custody hearing. Other than that, I see no way around this for the father.
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