Sure, there's nothing inherently difficult about detection but developing tests involves time and money. There have been a number of new substances (designers and prohormones) popping up in the marketplace over the last three years, so I'm not sure that people are racing to keep up with commercial products, unless the numbers warrant it.
There needs to be some basis for allocating resources. I also don't think that Don Catlin is doing this anymore - he has his business now, iirc - so UCLA's lab might not be operating in quite the same manner as in the past.
Listen, I could well be wrong on this. The decision of any NCAA athlete to use or not use a banned substance that may or may not be detectable isn't going to keep me from sleeping at night. It's their decision to cheat, and they run the risk of getting caught.
The fact is, I've just never seen an abstract or anything suggesting that one for epi has been developed. It would almost certainly be published within a few months of its creation, as was the case with the test for superdrol and others.