Interestingly enough, we have a phrag. schlimii that we call 'Golden Halo'. It came out of Ecuador in the early 90's (about the time we got fischeri), and it has always produced yellow in the staminodial shield and in the petals. To me, this particular clone fits the description for manzurii. The picture on orchidspecies.com certainly has intense yellow coloration throughout the petals.
The original description is in Lankesteriana 8(3):89-92. Wes Higgins article in 'Orchids' vol 78 #3 pg 174-175. Two images plus the image on IOSPE show a staminode without red markings or mid-rib. Just a round domed staminode.