It looks like it's working for you now. I had a similar issue in IE11 when the doc mode was set to IE9, and also in IE9. Print was working fine in FF, Chrome, Safari, and IE10+ (when not using IE9 doc mode).
The problem ended up being that I was using a remote proxy, with cross-domain headers in the web.config, so the remote proxy worked just fine in browsers with CORS; however, because the proxy itself required CORS to be served-up, non-CORS browsers (IE9, for example) failed with "access denied." The proxy worked as designed in posting the large json value, but only if the browser was CORS-enabled.
It took me awhile to realize this, but simply moving the proxy to the application server resolved the "access denied" issue. In my case, I had an application at domain1, a GIS Server at domain2, and a proxy on the web adaptor server, domain3. Embedding it in the application on domain1 (referencing via a relative path) removed the need to serve-up the proxy using CORS - now it works as a CORS workaround AND as a 2048 char workaround!
It should be noted that IE8/9 actually has partial support for CORS, but through XDomainRequest, not XMLHTTPRequest. XDomainRequest isn't supported by the dojo toolkit, hence the need to use a proxy.