I'm not in the South, but I do grow viburnum, not the Summer Snowflake variety.
I think the reason you see different things is that it is a very adaptable and tolerant shrub that will grow in a variety of situations, from sun to part shade. Even in the south, I probably wouldn't try it in deep shade. But the one I have now is planted in a pretty shady area under a large black walnut tree (viburnum is one of the kinds of plants noted for not being affected by the toxicity of the black walnut). It is doing ok there, grows and blooms, but is not thriving as well as it would in a spot with a little more sunshine.
Where you are in the deep South it might not like full sun, but again would probably tolerate it if it had to.