DY. I’m not the ribbono shel olam and I’m not a member of his committee. I don’t know the cheshbonos in shamayim and why things do or don’t happen. I believe that the ribbono she’ll olam created a shidduch for everyone. If you believe otherwise, that’s your perogative.
Why do you assume there was no bas kol for a child that died r’l? If a 20 something jumps off a bridge and dies, do you assume there was no bas kol too? My job is to help someone who wants to get married do so, not wring my hands in despair because someone is 37 years old.
As to what tosfos may or may not say, I have no idea. Why don’t you tell me.