Tile layout builder AJAX call without .when() wrapper

tilelayoutbuilder.ts

        $.ajax({
            type: "GET",
            url: "/" + controllerName + "/" + actionName
        }).then((data) => {
            console.log(performance.now());
            self.configurationObject = JSON.parse(data);
            self.tileLayoutRootElement = tileLayoutRootEl;
            self.buildTileLayoutConfiguration();

            if (data != undefined || null || "Error Message") {
                $("#" + self.tileLayoutRootElement).kendoTileLayout(self.tileLayoutConfiguration);
                let tileLayoutInstance = $("#" + self.tileLayoutRootElement).data("kendoTileLayout");

                for (let key in self.configurationObject.Tiles) {
                    self.getTileLayoutHTML(self.configurationObject.Tiles[key].TemplateID, key, tileLayoutInstance);
                }
            } else {
                console.log("Error");
            }
        });