| RS can't find a match? Seems unlikely, unless your bike is very recent model.
They insist that the colours change by model/year, and I have no doubt they have been right on that. Ducati red is not just one shade. However, I have taken a guess before, like going for 2003 ST2 dark blue because they didn't have 2003 M620Sie blue. It was right and the touch up worked a treat. All it means is that you take the risj on it not being right as it's your decision not theirs.
As for the official Ducati offering ... I arrived at RS because the silver touch up stick from Ducati for the ST2 was nothing like it. | 
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