I wasn’t able to find research comparing the two, either. My teacher brain, though, tells me there is a big difference. The benefit of listening to stories read online is to hear good models of fluency–expression and rate.
Benefits of read alouds by a teacher, with either whole group or small groups, are numerous, which I’m sure you are aware of, as well. Not only do we model and share stories beyond their reading levels to build vocabulary, but we can stop and respond to questions as students have them.
There are many strategies that naturally pop-up during read alouds–not just the ones we may have planned on discussing. We can engage students in the language of the story, especially if there are repeating phrases or ideas. We can talk about text features, relate the story to their background knowledge and made text-to-text connections.
There are many great articles discussing read alouds, if you’d like links to some of those. As I said, just couldn’t find any comparing the two.