The RadToolTip does not have a public client API which allows to move it around because the purpose of the control is to popup relative to an element. Despite this I prepared for you a sample demo which achieves what you need - you can find it attached.
Note, however, that it uses the private _setPopupVisible method and it is not recommended to use private methods because in case it changes on our side and upgrade you could face problems.
If you want you can use the provided solution or you could consider using the RadWindow control which exposes a moveTo method.
I hope that my reply is helpful and I wish you happy holidays!
the Telerik team