Heading into the last round of the season - after being the top points scorer and top performer for the backmarker team (Charouz) for which he was driving right up until Belov got a fluke 8th in the penultimate round - he agreed to do the last race for a very much front-running team (Hitech); Max Fewtrell had left Hitech and the guy who filled his seat for the penultimate round (Clovet) wasn't available due to FREC commitments.
Fraga was reportedly all paid up by his sponsors (Red Bull/Sony) at Charouz and cleared to race for Hitech when... apparently Charouz changed its mind and opened a contract dispute - seemingly frivolously (and it's not like they don't have form on that front) and pretty much on the day of first practice.
That meant he couldn't drive for Hitech and as a result both Charouz and Hitech ran the final race of the season with two drivers instead of three, so Fraga didn't get the chance to show what he could have done with an actually useful car.
I'm not sure why Red Bull ended the sponsorship precisely - I'd guess at the fact he was 24th (which outperformed the car by a mile, but still 24th) and they paid for 18 races but got 16 would have had something to do with it.