As you have found yourself, in such scenario what you should od is the following:
1) Make sure that you update the tooltip manager when you update the target controls (the grid in this case)
2) When the grid is modified, clear the old target controls (in operations such as sorting, paging, filtering, etc)
The demo you have linked is exactly the one which explains this but for sorting and paging. This being said, the solution you have found is the correct and reliable one.
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