Would it work if you were to use If condition? Like if rows are less than 1000 then save Excel. And if not then close excel without saving.

Or you could also use Go to -action and put Label -action where you want to go if condition is met. So if Excel RowsCount is more than 1000 then it does Go to -action and out the Label where ever you want the flow to continue after that.

Or do you mean that there would need to be timeout if certain action takes too long? And then after the timeout on certain action the flow would still continue?