Seems like an expensive experiment, indeed! If I understand, she's wanting to prove the efficacy of her EOs over other EOs in CP Soap - yes? I can see where she's coming from. You likely use what seems to her to be a large amount of EO, and FO, to scent a batch of soap. And, she's right. When I first made soap, I'd been making my body products for about a year. I was flabbergasted that almost 1/2 an ounce of EO was needed for 16oz of oils, whereas in my "potions", I needed no more than 10 drops of EO to scent 16 oz of oils. Now, mind you, I have no idea how much 10 drops of EO weighs, but I do know that in volume it's a lot less than half an ounce in weight!
Google "what is meant by essential oil purity" and you'll find some good articles on the subject.
But, here's the problem, this is her business. Besides the hard sell techniques of some MLM's, even if she's just a "here and there" seller she rightly has loyalty to her brand. So, if her EOs don't perform any better than what you're currently using there'll be a problem because she will search high and low for a reason in defense of her product. Just like anyone else would who owned a business. You couldn't tell my Uncle that there was a better bike than Suzuki because he was a Suzuki dealer and racer. Same with your friend.
I'd suggest doing as you've intimated and not doing the experiment. Unless you're using very low grade/adulterated EOs - which I'm pretty sure you are not - you're going to waste her precious product and possibly even cause a chasm in your friendship/acquaintance.
ETA: My post crossed cyber-space with
@AliOop. Her suggestion of making a batch with the lady and splitting it into absolutely equal amounts and into the exact same molds and then having her sniff them when cured might well work. Might..!