Can I just admit that I will probably never be able to take Nonnos' "Dionysiaca" as canon to mythology. Not only does he make Zeus father Dionysus with Persephone (Jeez even Ovid mentions that parental incest was considered deeply taboo), but according to

That’s the thing about all the lore written in the Hellenic, Hellenistic and Roman eras. There is just so much to parse and so many different traditions.

When I write, I try to find a good middle ground without straying too far away from the core mythos. And if I do, I usually have a good reason. The parentage lines you mentioned above will definitely never be part of my canon, I assure you.