I know a number of people use the Freestyle strips in their AT meter. I am not fond of that because the AT meter is made by a different company than that which sells the Freestyle strips. They used to be the same, but Abbott sold the pet meter business to Zoetis so who knows what they will do. I would trust Freestyle strips in the Freestyle meter. But it's your call and you have done tests.
Good to see her flat now, but the question is where she will be two hours after HC and when it wears off. Since you can test and feed while you are fine, I might stick to LC and see where she is before you go. Worst case, you give HC just before you leave to keep her higher while you are gone.
Side note, I used to take Neko's BG before her acupuncture and told her acupuncture vet what it was. It got so she could tell roughly where Neko was by how she felt.