The way to check which ID your receiver is  set to is on page 56 instead of 57. Sorry.
Actually, the Vol+ signal I posted is for ID1 and not ID2, so that's already a strong indicator that your receiver is on ID1.  But it certainly won't hurt to try the ID2 Prologic Hex.
The only thing I can think of is perhaps the receiver needs to be in a particular mode to respond to Prologic.  So use the OEM remote and step through the procedure to reach Prologic, trying the Prologic discrete at each step.

SysIntegration, the first of two links at the bottom of my last post goes to a Yamaha page which describes the 371 and 3064 as being basically the same.