Yes, I don't see any problem with doing Zettelkasten using Dendron. I personally didn't fully embrace what Zettelkasten does (I'm not a writer, and I didn't get much benefit from the method), but I briefly tried it out. There was nothing special I had to do to fit it in with Dendron. With the hierarchical nature of Dendron note I would imagine it would be even simpler to implement a digital Zettelkasten.