It doesn't matter at all what kind of promise flavor an API returns because promise implementations treat other implementations as interchangeable.

Even the ES6 Promises implementation supports this:

    Promise.all([{
        then: function(r) {
            r(3);
        }
    }]).then(function(result) {
        console.log(result);
    });

Here the plain object with then could have been any promise implementation, even jQuery, and it still works.