I'm not trying to be obnoxious (too late!), but I thought there really was an intent around requiring a slam to be open to all ages in order to be NPS-eligible (though exceptions are pretty regularly granted). Is that covered over in venue certification instead?
Amy is on the right track here. There is no confusion in the wording. The team must be selected from an ongoing reading series whose venue has the characteristics of
Teams must be chosen from an ongoing slam or reading series open to all poets regardless of age, sex, race, ability, appearance, or sexual orientation.
The "series" is "open to all". It does not say the team that comes out of that series may be all ages. This is a general statement of which venues may send teams to NPS, ones that meet PSI certification. It does not have anything to say about who may be on that team, nor about what the separate and specific requirements are for team members or individual poets at a specific event.
For someone to compete in NPS, team members must be 21 plus, unless 18 plus is ok'ed by the host city because of the availability of 18 to 20 year old friendly venues. This language was passed by slammasters in the spring meeting of 2005, I believe.
For someone to compete in WOWPS, that poet must live life as a woman. The fact that the venue qualifies to send a woman by being "open to all" doesn't mean they can send just anyone to this event. That seems pretty clear.
In like manner, you can't point to the language cited above about a venue being "open to all" and say the qualifications for team members for NPS are unclear. They are not. One statement refers to the operations of the slam venue, the other clearly states the restrictions/qualifications for team members.
I understand pulling for your team members. Glad to hear your poet is 18 years old, and is able to compete.