In your API, you are returning the result of command:
git log --follow --date-order <sha> <path>
If the file was renamed/deleted in the branch, the command returns nothing. But if use the command a bit differently, we can get successful results:
git log --folow --data-order – <path>
My proposal - allow use for property commit value * or "" (%22%22) and in this case, we can read the history of the file by the old name.