The discussion of vocabulary has come up before on HO. I think–opinion–that if you don’t use dashi and chicken what you end up with is not oyakodon. That doesn’t mean it isn’t good. You could poach Portabello mushrooms in veg stock as a base with a mirepoix. You could add black beans (although I wouldn’t) and pour that over rice. It would make a great rice bowl but not oyakodon.
My computer keeps insisting I’m talking about oxycodone. sigh
