Mark...
Love the colour photo of the Me262...
I'm inclined to support your belief that it is 1./KG51's '9K+FH'. The aircraft I/D letter is clearly white, as is the matching tail fin tip. If it had been F1+DA, the 'D' would likely have been medium blue to confirm Geschwaderstab status, but it's clearer in this photo that it's not a 'D' we're even looking at.
Regards...
Paul