It's not just a question of grammar; it's also one of usage. If they'd used مرتدٍ, which is also an agent noun/present participle, it would have been perfectly fine. If they'd used the verb for either word, تلبس or ترتدي, it would have been perfectly fine. It's this particular agent noun of this particular verb that is not idiomatic in this context in MSA. But agent nouns do have their place in MSA usage as well.
هل أنت عائد غدا ؟ = Are you coming back tomorrow?
هل تعود غدا ؟ = Will you be coming back tomorrow?
The former emphasizes the act of returning itself; it's what a longing lover would ask of her paramour, worried that he's never coming back, whereas the latter emphasizes the time of the return, glossing over the act of return itself as something to be taken for granted:
- Is it tomorrow that you're coming back, or some other time?