I dont have any experience with Catt and Encyclia but I have vandas based on my experience after a week of selfing or sibling crossing the ovary will swell and usually will progress increasing in size about 3 to 4 inches in length then focusing in maturity.Problem always arise when plants from Thailand you do crossing with the same species from the wild example the ovary is not progress as what we expected (could be they added the chemical or radiation during mass propagation) . The fruits relatively very small sometimes inside there nothing except fibers no viable seed at all.Usually crossing with primary hybrids shouldnt be a problem, again for intergeneric some of the flowers can take it but others not all depend on the time, temperature when you did the crossing for example if you just spraying the fertilizer immediately you do some crossing basically will be aborted after few days this is based on my observation. For vandas I prefer as you said green seed pods always the best the chances for contamination is reduced, basically I will harvest after 4 months and send to the lab for sowing.
The first photo is after a week of selfing.
The next photos is sibling crossing V.denisoniana wild got pollen from Thai crossing, very small seed pod and minimal seeds or maybe none. The last photos Thai denisoniana carried seed from wild deniso both of them matured together but the seed pod very small.