I clean alot of headboards, although not many dralon ones. I found them much easier once I was using some kind of enclosed jet upholstery tool. e.g. CFR, PMF, The difference is that you don't get any over-spray/spill which happens because the fabric is tightly upholstered. Also you can go over the grease area several times without over-wetting and at very high heat.
Otherwise just clean as normal upholstery (with the usual precautions)
Nigel