Guest post by "Rachel Newstead" To Kyle: I'm assuming Wendy thinks that the school still considers Sarah Seth, since she doesn't know (yet) that Sarah's presenting as a girl there. I don't think it necessarily implies a lack of support. Wendy probably would prefer that Sarah start fresh at a different school, no doubt, before she'll allow Sarah to present as a girl full time.
It could also be part of the deal she made with Clark, come to think of it.