The route that you are trying to setup is just for the 888 ara code, with no country code.
On the Cisco, the dialpeer needs to be setup the same way, with only the 888 pointing to a PSTN port.
1)Be sure that the Quintum is online. Go config, print and look for “unit 1” “online=1”
2) Take a event log: Type ev +ch
that will enable the call handler log.
ev to get to the log
ev c to clear the log and start new.
3)Be sure codecs are the same on both ends.
On the log ,look for the rejection code.
Ping from the quintum the other unit. it should be able to ping to pass calls.