I got matched HH Diamond to IHG platinum within 48 hours this week (IHG platinum courtesy of Virgin platinum which in turn was a status match to QF platinum
). I have had a HH Diamond status match before so I doubt that people are being knocked back on the grounds of previous matches. I don't have any IHG card either, I just took photos on my phone of a confirmation email from an IC hotel and an IHG email showing my status and uploaded those photos to the online HH status match application form. It did say somewhere that they want .png files only which luckily was what my phone took as I would have had no idea how to change the format. The only other things I can suggest is that it may have helped that the IHG IC stay I showed to them was my most expensive IHG stay from the last 12 months and also that I had stayed in a Conrad in the last 12 months which was pricy too. So they may be interested in matching people they perceive as being willing to spend more. But I'll likely disappoint them as I've made several of my forward HH bookings at Doubletree