I don't think you can, because Cloudflare Video CDN is a separate product. So offering it a long with your business / free package is against your business interest. Cloudflare basically tried to sell me a $1000 / month (minimum) Video CDN. But if it was a mistake and should this be able to work using Cloudflare I would happily pay to upgrade to the business plan. I can afford 20-40 USD / month not $1000