While the documentation doesn't list a destroy
method for kendoToolTip, it does exist.
I would suggest creating your Tooltip like this instead:
$("#grid").kendoTooltip({
filter: "td[role=gridcell]",
content: "My Other ToolTip"
});
Then you can destroy the Tooltip with
$("#grid").data("kendoTooltip").destroy();
If you create it like this:
$("td[role=gridcell]").kendoTooltip({ ... });
it will create a widget for each cell (because your jQuery selector selects all cells!), so when you try do this:
var myTooltip = $("td[role=gridcell]").data("kendoTooltip");
myTooltip.destroy();
it will only return and destroy the widget for the first of the matched elements.