Here is an excerpt from the Interval Exchange Guide for DVC Members:
(c) II does not issue Confirmations for (i) an exchange into any DVC Resort located in the Orlando/Kissimmee, Florida, area to any Interval Member who owns a week-specific interest in a Member Resort located within the Orlando/Kissimmee, Florida, area; (ii) an exchange into a Member Resort located in the Orlando/Kissimmee, Florida, area to a DVC Member owning a week-specific interest in a DVC Resort located in the Orlando/Kissimmee, Florida, area; or (iii) an exchange by a DVC Member to any DVC Resort, it being understood that all such transactions will be conducted by DVCM or its third-party internal exchange provider in accordance with rules and processes established by DVCM, in its sole discretion.
I read this as Interval International will not confirm an exchange into the Orlando/Kissimmee, FL area, if you have an Orlando/Kissimmee resort with DVC. I don't see it addressing if you own at Vero Beach, Hilton Head, or Aulani.