Your DCT letter doesn't count as one of your letters of rec, unless maybe they're your research advisor and are writing you a second letter with that hat on. I applied this past year and had one letter from my research advisor (who is a neuropsychologist) and my other two from neuropsychologists who supervised me on practica. I waffled about whether the third letter should come from that neuropsychologist or a therapy supervisor, but since the third neuropsychologist also supervised some intervention work that I did, I decided that choosing him would cover all my bases. I have friends who went the other direction, though, and we were all equally successful in terms of interview offers.
The two npsychs who weren't my research advisor are also boarded (ABPP-CN), which shouldn't matter according to the APAGS internship book (get your hands on a copy of this if you haven't yet), but I was told that in as small a world as neuropsych where many boarded folks tend to know each other, it's a good look.
