takes advantage of laws meant to help the disabled for personal gain.

See the detailed discussion of her crimes against the disabled on our forum

Can a service dog fly in the cabin of a plane for international travel?

That depends on the country of departure's laws and the country of arrival's laws. Some countries require all dogs, including guide and service dogs, to enter the country as cargo.
Check Consular Information Sheets for the individual countries involved to find where to check the regulations for dog import/export. See the link below for Consular Information Sheets.