Ten pages, ten addresses, and a bill of zero — that part is easy once the order is right. Facebook does accept an address on your own domain; what it refuses is temp mail and rent-a-domain sites, so leave that one you found where it is. 
How I would build it:
grab a domain — the .TECH topic here hands out the first year free
point Cloudflare Email Routing at it — unlimited addresses, all landing in the Gmail you already read, no mailbox to babysit
if you want a real inbox on the domain, Zoho’s free plan gives five users at 5 GB each, and aliases cover the other five
or stay forwarding-only with ImprovMX or Forward Email
Then the bit that saves an entire evening. Meta Business Manager → Brand safety → Domains → add your domain, and Meta prints one line:
facebook-domain-verification=<code>
Drop that into your DNS as a TXT record, press verify, and every page under that domain is covered by it. One record, ten pages, no ten rounds of email ping-pong. 
Keep them inside a Business Manager too, each page with its own address — ten pages hanging off one personal profile is what starts looking like a farm.
Register the domain and set the TXT in the same sitting tonight; each page after that is ten minutes. 
!