I have bought a good watch. No room for box in baggage.

I recently bought Rolex watch in Shanghai. My bags are full and I have no room for the big box it came in. The dealer said that if I don't bring the origjnal box I might not get my VAT back. Am I able to present just the watch in its original plastic wrapping, the receipt and warranty card and leave the box with my relatives in Shanghai and still get the VAT refund?