While it is true that staff members don't hold all answers they are expected to be aware of the site rules and policies, especially the Site Support team whose job is often to explain said policies to the members. c:
In any case, as Mood's explained Iwaku has several ways to verify the age of the members. You can read about a few in the
resource. While at the very base we only ask members to sign up with their correct birthdate, we also do our own investigation when we have reasons to suspect someone of lying and can ask people for a Photo ID (like explained in the resource). The reason why we don't do it at the forefront is because of privacy, as you can imagine that it can be quite invasive.
Should you still want to speak an admin about it, if you click open the list in 'Members' in the top bar you will see
'Administrators and Staff' if you click on that the purple names (and in Diana's case teal) are the administrators.
Oh, hey. Just as I'm writing this Diana posted a new resource on this very topic:
Verified Age Marker on Iwaku
At last, in regards to your Discord server. What Mood's has provided you for a solution is, unfortunately, the best way to go about it. Since Discord itself doesn't do anything with age verification. Though, that also means that you can't advertise your Discord roleplay here on Iwaku if it contains any mature themes that requires age verification (usually smut)
since Discord doesn't do age verification.
Iwaku's discord does have a 'NSFW' channel, however to which only adult members have access to. You can advertise your Discord rp there.