I haven't worked with InSim (yet
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), but in the absense of any other replies...
I did notice that the "Verification ID" that you received is being decoded as a two byte value, and the one you're sending back is a four byte value. Unfortunately I can't find the InSim docs online, so I can't verify that's correct behavior. The only other thing I can imagine is the byte order being incorrect, but you're sending it in network order, so that's almost certainly not the case.
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rheiser