Winter Plant ID help

struggling to ID this sucker, any help would be much appreciated! [found in Denver, CO, US -- in close association with a large Ailanthus -- very fleshy berries despite the cold]

 

Maybe Cornus mas.

 

Solanum dulcamara?

What is inside the fruit?

 

Viburnum sp., most likely V.opulus

 

a single flattened seed, fruit is very juicy, there's a strong odor that I can't quite describe (it's slightly sweet/unpleasant I guess)

twigs look like they might produce small compound umbels in bloom, buds naked + alternate

 

That's my first thought too. The single flattened seed also fits that well.

 

Thanks all.