For anyone else that may needs to know the control that raised the ScreenTipNeeded event, see the following snipped:
Private Sub Control_ScreenTipNeeded(sender As Object, e As ScreenTipNeededEventArgs)
Dim objComponentInputBehaviour As Telerik.WinControls.ComponentInputBehavior = sender
Dim objControl As RadControl = objComponentInputBehaviour.SelectedElement.ElementTree.Control
Debug.writeline(objControl.name)