The conversation with William II went smoothly, which greatly improved Arthur's mood that had been at an all-time low due to Queen Victoria's critical illness.
Seeing that Queen Victoria wouldn't last much longer, even though Arthur and Queen Victoria had deep feelings for each other, he had to consider Australia's future.
Once he lost Queen Victoria's protection and support, he would essentially lose support from the United Kingdom.
Although Prince Edward appeared to have a good relationship with Arthur on the surface, he definitely would not go to great lengths to help Arthur and Australia rise.
Arthur certainly had leverage over Prince Edward, but if such leverage were made public, not only Prince Edward's status and reputation would be greatly impacted, but even the status of the British monarchs, nobles, and monarchs worldwide would be greatly affected as well.