Thank you for the provided Dojo.
The Sortable widget listens for the mousedown event and this is why you are not able to click on the inputs but you are able to tab and edit.
To enable the clicks into the inputs of an editable grid while using a Sortable, just exclude the editable row from the filter:
filter: ">tbody >tr:not(.k-grid-edit-row)",
Here is the updated Dojo for your reference:
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