The initial announcement (
https://disneyparksblog.com/disney-...g-magical-cruise-vacations-to-southeast-asia/) said:
Under a recently signed Memorandum of Understanding,
Disney Cruise Line and Singapore Tourism Board agreed to collaborate to homeport a brand-new
Disney cruise ship exclusively in Singapore for at least five years beginning in 2025.
I'm not sure if that means "this particular new ship" or "a new ship." Even if the agreement allows switching out the Adventure for another new ship, that the Adventure was designed to meet the market in south Asia, that would be unlikely to happen.
Basing the Dream or Fantasy in Galveston is very plausible. Basing the Wish in Galveston after the next 2 ships launch (and having one of newest ships do 3 and 4 night cruises from Port Canaveral) is feasible. Basing the Adventure in Galveston and basing one of the new Triton-class ships in Singapore seems like a pipe dream by the Galveston port representative.