Many rides use sweepers/helpers/keepers/LTs (let’s just call them sweepers) to help the ride leader control the ride and bring riders back to the yellow beacon if they have fallen behind. Some rides use an official red beacon and some use volunteers from among the regular riders. Some use a mix of both. In all cases, it can be difficult for other riders, especially new riders, to identify the sweepers when they need assistance.
To make it easier for those sweepers who do not have the red beacon and for those they are trying to sweep, perhaps Zwift could provide specially marked kit that any rider can access in their garage. When they sweep on a ride they can change into the easily identifiable sweeper kit, jersey, hat, whatever, before the ride. This ensures there is no additional admin burden placed on ride leaders/organisers or Zwift staff by having to manage multiple red beacons (noting this isn’t available anyway at present). This would be a very simple, but highly effective approach that places the responsibility with each rider that chooses to sweep.