So.. I was looking around on the web for the text of Dong's memorial steles (which I found here BTW if anyone is interested) and discovered that on the website of Wan'an Cemetery (where he is buried) you can make virtual offerings at his grave
http://www.wanancemetery.com.cn/shequ/j ... ?jngid=466
The icons below his picture allow you to offer flowers, incense, candle, or wine.