Well when I got this plant from Orchid Zone so many years ago that's what Terry was calling it, so you better correct him too while you're at it.
Also, back then...RHS was calling all the glanduliferum complex the same damn thing. So until further offical notice, it's Praying Isabel for me.
If you do a google search you find Praying Isabel made with both types, wilhelminiae and praestans and awards given as such. AND nobody alive has seen a "glanduliferum". So why both using this name at all?
I agree, I think that is what started the confusion. Paph. Praying Isabel was registerd by Booth back in 1994. Back then the whole "glanduliferum" complex was considered to be one species. Now, according to Braem, there are actually 3 separate species. The darker form (native to the main land of New Guinea) is known as Paph. wilhelminiae. The lighter colored (and more yellow in color) is known as Paph. praestans. Paph. praestans also tends to get larger flowers on larger plants. According to Braem there is a different and distinct species called Paph. glanduliferum, but it has been lost in cultivation for over 100 years (and who knows it may be extinct, if it really existed). Besides the original description, there is only one "Type" herbarium specimen known of this species. Based on this herbarium specimen and the original description, the main distinction between glanduliferum and praestans is the shape of the staminodal shield. The RHS considers both species to be the same (and they probably are correct, as in my opinion you can't base a whole "species concept" on just one herbarium specimen, and on just one characteristic that is probably variable within the species), and also, like you said as Paph. glanduliferum has not been seen for over 100 years, I would just leave out "Paph. glanduliferum" and call it Paph. praestans for registration purposses.
Now as Paph. Praying Isabel was registered back when there was only one species accepted for registration (Paph. glanduliferum), when Booth registered the cross the parent name became Paph. glanduliferum (which is now considered by the RHS the same as praestans). Now if Booth did make it with Paph. wilhelminiae, and can prove that he did, he can let the registrar change the parents of Paph. Praying Isabel to wilhelminiae and Lady Isabel. Until then the accepted parent names will stay as praestans and Lady Isabel. If you have a cross of wilhelminiae x Lady Isabel, it is thus considered unregistered at this moment.
When Terry had (what he called) Paph. Praying Isabel, he may have remade the cross using wilhelminiae, but as back then it was considered the same as glanduliferum (aka praestans) he just called the hybrids Paph. Praying Isabel (which back in the 70's and 80's was still correct, but not any more).
Robert