Vandas wont flower unless they get enough light. If yours is flowering then Its happy
Im not huge on vandas, but my thoughts would be, is the one in spike the shadier vanda type, or the sunnier vanda type.
If its the sunnier all your vandas have plenty of light, but if not, maybe move your other two.
For the one thats in spike, I would leave it where it is until it flowers and then maybe move it somewhere where its beauty can be better seen.