Thank you for the replies. I'll call Silk and So Delicious to be sure, but
I've eaten other products from both in the past, so I'm hopeful. I know So
Delicious is really good about avoiding cross-contamination in its ice cream
manufacture, at least.

I really appreciate the suggestions. I have a severe enough allergy that I
react to the tiniest bit of any milk derivative, and didn't feel like wading
through the information-light websites of all the available yogurt brands
claiming to be soy after confirming that at least one (O'Soy) has serious
contamination problems.

Thank you all!
Weavre Cooper