Yeah, there are more levels to "surface treatment" than just treated or not treated. Photographic emulsion seems to be very demanding and needs a particularly "good" surface treatment. Some products that are treated for inks, may not work for emulsion. Heck, they don't even work with all inks...

So, for example, there is polyester sheet available that is corona treated at factory to make printing possible. So it seems that the corona treatment is not completely volatile. It remains good enough for most inks, but not good enough for emulsion (and some inks).

But given that 3M product, it's probably easiest to just buy and use it. Do you know of any retailers who sell those with international shipping?