There's no limit to the number of authorized scorekeepers for any tournament, whether it be PAPA, INDISC, or any particular selfie league. Like all those events with volunteer scorekeepers, players won't be allowed to record their own scores.
For selfie leagues in particular, you better have 'staff' on hand to record ALL SCORES if you want any hope of having that qualifying data count towards TGP. Any attempts at 'buddy scorekeeping' is simply a "NO" from me.
You're welcome to full on organize specific hours of every day for qualifying to occur, with a solid schedule of scorekeeping volunteers to make that happen. If I personally see that as legit I may allow that to be counted, but it's completely at my discretion, and highly depends on the mood I'm in . . . which highly depends on how well my kids are sleeping