If she does have to disconnect on big coasters because of G-force pushing insulin through the tubing, I'd still keep the pump on my person, in a well-secured bag, instead of leaving it somewhere, and then reconnect as soon as we got off.
An upcoming Disney trip was the main reason I switched to Omnipod from Minimed Paradigm when my warranty ran out; I wanted to be able to swim and get wet without disconnecting. The only restriction my doctor and rep/trainer told me about was not to go through the backscatter/high intensity X-ray at MCO and opt for the patdown instead, and everything went great. YMMV, of course.