I’m a little unclear on exactly what the requirements for Worship are when it’s an Associated Cult’s holy day. Sanctify doesn’t seem cult-specific, so your own Sanctify would work. Do you need an initiate of the regular cult to lead the Worship when yours is associated, and/or do you need members of the regular cult to participate? I think it makes sense to require this, but the rules aren’t explicit. If you can both make your own sanctified area and run your own Worship, then the need for travel is obviated (although you earn one less RP).