Few Cloudy
The RJ fuel is fed through a heat exchanger on the engine. It is unlikely the fuel 'geled'.
"IF" these guys suffered an aerodynamic stall then it is also possible the engines flamed out, even with CONT IGN. (Depending upon aircraft attitude, etc)
One possibility is that during an APU in-flight re-light at or below 13,000 the crew didn't get the bleeds transferred to the APU from the engines as stipulated in the QRH. If so, they'd never get an engine started.
Cheers
