I don't know if the rspo certifies pko, but I use rspo palm.
First, the US consumes less than 5% of the world's palm oil. So us boycotting it would not even be a drop in the bucket. Our usage has 0 effect on the deforestation.
Second, supporting rspo palm gives the organization power to influence the growers that are damaging the rainforests.
Third, palm farming supports families living in the most desperate poverty. If they loose the little income without some kind of way to replace the income, they are going to suffer even more. Rspo knows this and is trying to come up with a way to surmount this.
And finally, there is nothing we have right now that takes the place of palm. Not just in soap, but all of its uses. And it is incredibly efficient. No other crop used to produce oil matches it. If palm went away, something will have to replace it, and anything we have now would take many times the amount of land to grow.
It's all catch 22 I know.
I'm not saying you have to use palm. Do the research, look at both pros and cons. Realize both sides are slanted to get you on their side.