I think it was $100K purchase history to do a SO, wasn't it? I thought that was the new policy.
For clarity though, a SO is not a MTO. A MTO is pre-approved (e.g. WG oynx, Cosmos WG oynx diamond BTF ring), vs a SO is not pre-approved (e.g. WG carnelian, WG blue agate). I thought SOs were on hold late last year and would open up in 2022, so if it has not opened up yet, all SOs are a no at the moment. They may have opened up by now though, your SA would know. MTOs however, are always available; you just need to order and have it made.
What combo 20 motif are you thinking? It may be a MTO and you can just order it. I would ask your SA before you fly out to Houston to be sure. So excited to see what you're getting! Have fun!