Hi, you can always use the RHS orchid register to look for parentage of your orchids, but you need to be very sure of the name and its spelling, or else it is difficult to use it. The correct name of the plant you are looking for is Vandachostylis Sri-Siam and its parents are Vanda tessellata and Rhychostylis gigantea.
Here is a link to the register
The International Orchid Register / RHS Gardening