I doubt anyone knows that info, if its triple point data is not published. You might try looking at data for similar molecules, if you can find it. Generally, I don't think people worry about that if they're trying to sublimate a material. Instead they create the best vacuum they can, and give consideration to staying below temperatures that would degrade their material.

Column chromatography allows for using UV light as an additional demarcation between fractions. You don't have that with sublimation. To measure triple points you need highly purified material...which is probably refined by CC

You might find triple point data here.