Bonus plants are always nice.
If they are clones, it is fine to leave them together for a better display but I usually like to divide them. The only ones I haven't divided are the C. mossaie as I do not have room for two of them but that was probably a bad idea as they are not clones but siblings.
Someone told me that the way to tell if the orchid is mature is if the new pseuodbulbs stop getting larger and they are blooming. You might just be lucky to have a smaller zygo hybrid.