Chances are Trimac will outgrow it, and try to kill it if it can.
If it wasn't purchased from someone reputable, its not a trimac. Where did you get it from?
I recently bought a Trimac from a LFS and wondered if it was a low grade FH. All the pics of juvi Trimacs I've seen is exactly what it looks like. Yours is not showing a large hump forming yet and for what it's worth looks like a Trimac to me. I think Trimacs are among some of the best looking cichlids around and I am not a big fan of those Frankenstein Flowerhorns. I also have two Rotkiels in the tank with my Trimac and he doesn't even notice them yet, however long term I think it's the temperament of the individual that will determine weather it will work along with a big enough tank. Anyway, great looking fish and nice set up. Good luck.