I dont know what is max voltage on drain of fet inside dpaswitch.
Be careful your reflected voltage + spike voltage + input voltage does not go over this level.
But in theory a flyback for that is feasiable yes.
Be wary of the amount of ringing voltage across the secondary diode......the leakage inductance referred to the secondary will be much because your NS>>NP.
You may well need to interleave wind the transformer.
Di d the powerint.com PIXIS design software say anything about the suitability of the dpaswitch?
I havent yet been through the dpaswitch datasheet here, sorry.
You know power.com have their own forum for their kit?