That airport is not default.
Any hancrafted/premium airports in the sim, even if they free or made by Asobo or Microsoft, are to be considered exactly like 3rd party airports, so you can't use GSX replacement jetways there, which are only made for true default airports.
That's why, the FSDT Installer will automatically disable such airports when running the "Exclude 3rd party" routine, and they should stay disabled.