We know that Jews are able to say brachot on behalf of each other due to the concept of "Kol Bnei Yisrael Aravim Ze-Le-Ze", or "All Jews are guarantors on behalf of one another", so that if Reuven makes a hagefen over wine and has Shmuel in mind and Shmuel says "amen", the latter has fulfilled his obligation.
May we, though, extend this concept to non-Jews, who are neither commanded to make a bracha before/after enjoying this world nor halachic guarantors to one another? If Ralph and Abdullah are studying together to convert to Judaism, may Ralph be yotzi on Abdullah's "Borei Menei Mezonot"?