I haven't found any references that suggest that another specimen would be needed for pollination. But if it's not blooming (note that the flowers aren't terribly showy and could possibly be overlooked) that in itself would explain the lack of fruit. The Hillier Guide to Trees and Shrubs does say that Symphoricarpos albus is "not as free-fruiting"as S. albus var. laevigatus... though that's not much help to know!
We have one of the S. x doorenbosii hybrids (with pink fruit), and unfortunately, it doesn't produce much fruit either.
