I may have missed it mentioned earlier, but it seems that only Dan thinks DE is at all related to chalav stam issues. Certainly, some rabbis will tell someone who doesn't eat chalav stam to avoid DE because taam k'ikar. Rabbi Belsky told me there's very good reason to avoid DE for this reason and that was a part of the ou's decision process when dropping the DE designation so as not to make it seem like it's for sure ok.
the oreo story has been around for years with conflicting reports. please ask for yourself and don't serve it to others when they're expecting parve.