Could you add some Middleware to taget your particular file and add some No Caching Rules 

You can do something like this but change to your requirements 

    public class NoCacheMiddleware
    {
        private readonly RequestDelegate _next;

        public NoCacheMiddleware(RequestDelegate next)
        {
            _next = next;
        }

        public async Task Invoke(HttpContext context)
        {
            context.Response.OnStarting(state =>
            {
                var httpContext = (HttpContext)state;
                httpContext.Response.Headers.Add("Cache-Control", "no-cache, no-store, must-revalidate");
                httpContext.Response.Headers.Add("Pragma", "no-cache");
                httpContext.Response.Headers.Add("Expires", "0");
                return Task.CompletedTask;
            }, context);

            await _next(context);
        }
    }

Or without Middleware and directly in Startup 

        app.UseStaticFiles(new StaticFileOptions
        {
            OnPrepareResponse = context =>
            {
                if (context.File.Name.EndsWith(".xlsx"))
                {
                    context.Context.Response.Headers.Add("Cache-Control", "no-cache, no-store, must-revalidate");
                    context.Context.Response.Headers.Add("Pragma", "no-cache");
                    context.Context.Response.Headers.Add("Expires", "0");
                }
            }
        });

There's an open source addon that tries to solve it in a different way - you can refer to sources for inspiration https://github.com/episerver/EPiServer.CdnSupport

Basically, it modifies URL to include last modification date as a first URL segment - so it still be cached and delivered by CDN, but when it will be changed, new URL will be generated.

Won't work for your case if users bookmark URL; but will work if they use a download page with URLs generated by CMS.

Another similar approach, to not touch this globally - just add any query parameter to generated URL, like ?t={file_last_modified_date} - different query forces CDN to download file directly from server.