Why do I need enroll payment details, if i am not planning to monetize my app with Roku Ads

Hello.
I’ve built my first app, and I am planning to monetize it with 3rd party VAST server.
But when I am selecting in monetization section that my app contains ads, it is automatically said that I need to enroll payment details,
Now I need wait for review of my W9 form, but actually there are no need. Because I am not planning to receive payments from roku for advertising.

Is there are any way to publish channel without enrollment. And how long it usually takes for W9 form review?

Because Roku will try to fill in the unfilled ads. That’s what Roku said, though I haven’t been able to verify yet.