JSFiddle - React, Tailwind, and code Playground

HTML

<link rel="stylesheet" href="https://kendo.cdn.telerik.com/2016.1.112/styles/kendo.common.min.css">
<link rel="stylesheet" href="https://kendo.cdn.telerik.com/2016.1.112/styles/kendo.rtl.min.css">
<link rel="stylesheet" href="https://kendo.cdn.telerik.com/2016.1.112/styles/kendo.silver.min.css">
<link rel="stylesheet" href="https://kendo.cdn.telerik.com/2016.1.112/styles/kendo.mobile.all.min.css">
<script src="//kendo.cdn.telerik.com/2016.1.226/js/jquery.min.js"></script>
<script src="//kendo.cdn.telerik.com/2016.1.226/js/jszip.min.js"></script>
<script src="//kendo.cdn.telerik.com/2016.1.226/js/kendo.all.min.js"></script>
<div id="grid"></div>

JavaScript

$("#grid").kendoGrid({
    toolbar: ["excel"],
    excel: {
      fileName: "Grid.xlsx",
      filterable: true
    },
    columns: [
      { field: "productName" },
      { field: "category" },
      { field: "subcategory"  },
      { field: "unitPrice"}
    ],
    dataSource: [
      { productName: "Tea", category: "Beverages", subcategory: "Bev1", unitPrice: 1.5 },
      { productName: "Coffee", category: "Beverages", subcategory: "Bev2", unitPrice: 5.332 },
      { productName: "Ham", category: "Food", subcategory: "Food1", unitPrice: -2.3455 },
      { productName: "Bread", category: "Food", subcategory: "Food2", unitPrice: 6 }
    ],
    columnMenu: true,
    excelExport: function(e) {      
      var sheet = e.workbook.sheets[0];
      
      for (var rowIndex = 0; rowIndex < sheet.rows.length; rowIndex++) {
      debugger;
        var row = sheet.rows[rowIndex];
        var numericFormat = "#,##0.00;[Red](#,##0.00);-";
        for (var cellIndex = 0; cellIndex < row.cells.length; cellIndex++) {
            var cell = row.cells[cellIndex];
            if (row.type === "data") {
                if (cellIndex == 2) { // how are we able to identify the column without hard-coding indexes?
                    cell.format = numericFormat;
                    cell.hAlign = "right";
                }
            }
				}      
      }      
    }
});