I am afraid that mixing both edit modes is not possible with the Kendo UI Grid. What I can suggest is to have incell edit mode set for the grid, but implementing the actual "add row" functionality with custom code. For example you can have a few input fields outside the grid and when user is done populating these input fields to use the add method of the Kendo UI DataSource to add an object to the grid's data. The object added to the DataSource should contain the values typed in the input fields.
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