Acme.sh dns alias

[MacEncrypt]

we have mail host mail.masterhost.com
we have clients email domains hosted on mail.masterhost.com
example :
mail.boring.com
email.someother.com

most of the clients DNS are not hosted with cloudflare however mail.masterhost.com is and is configured for api access with cloudflare
for clients not on cloud flare we were doing a standalone port 80 setup but would like to use alias
those clients have A records for their domains pointing to mail.masterhost.com public IP address

if i add the _acme txt records to point to the mail.masterhost.com (on the non cloud flare hosted domains)
_acme-challenge.mail.boring.com >>>> _acme-challenge.mail.masterhost.com
_acme-challenge.email.someother.com >>>> _acme-challenge.mail.masterhost.com
Is this enough ? I’m confused by the alias part do i need to add another record ? what would i cname if i have to ? i cannot change the mail.boring.com address as this is already configured on the clients devices …

[Osiris]

@MacEncrypt

Is this enough ?

Yes, as far as I know, the DNS resolver of the validation server follows CNAME records for DNS authentication.

[cpu]

@MacEncrypt

Is this enough ?

One way to find out for sure would be to try using the staging environment to test issuing a certificate.