Edit: cyb youre too quick for me!

Will leave explanation here for the records..
Ronsonol seems ok to use as verified by cyb previously so a simple back track is needed. I suspect a good 60% of the yeild will be in it due to the heat used.
Firstly decant the naptha into a seperate 1litre jar and cool it in the fridge until its cold so the solubility of the alks is reduced to aid the next step.
Make up a solution of water and vinegar, 2 caps of 4% distilled white vinegar in 500-600ml should do to get it to around pH5.
Pour this quickly but carefuly into the NP jar, put the lid on shake it vigorously many times. Leave to settle and do it again in 5 minutes.
Repeat over the course of an hour.
Decant naptha, the alks should now be in the water-vinegar solution.
Save that naptha somewhere safe incase you need to repeat again.
Next is rebasifying by adding lye again, I think 70-80g would suffice in 600ml to freebase the alks.
Let it settle and cool to room temp or slightly warm.
Pull with 150ml of naptha and evap and/ or freeze precip.
By now the original jar should be cool and you can carry on following cybs salt tek to extract the rest.
I dont know what weights you are extracting from and volumes you used so assumed 50-100g of dry bark to base above the volumes on.. Some could be excessive I tend to over do amounts to be sure.
edit: You could also finish the process as is and clean the product at the end by recrystalizing or a salty sodium carb wash.