I've been looking for these ever since that post and finally found some. The Dynamo ones were from Dollar Tree. Although the Carbona one may look a bit darker I think that is largely how thin that is compared to the Dynamo.
I did a quick dunk test and knew the batik would release some. It wasn't a whole lot difference before and after so I think both brands caught what there was to catch.
All in all -- it will alert me to any potential problems and I will use again. Or I will stop buying batiks... Dollar Tree here I come!