A.O.
I think Itsacrazylifewith4 has it right. Instead of putting them into the cake batter, crush it up, mix it with the frosting and put it in between the layers of cake and on top. That sounds yummy!
You could try a new version of frosting by taking some whipped cream and add a packet of chocolate pudding mix. It is a lot fluffier and not as sugary. Good luck and Happy Bday to Hubby.