I dont think it is possible with default options available.
Once the process chain is started from redwood, then there is no real control on redwood side.
The process chain in BW system creates the child jobs which are copied to redwood as CCMS jobs.
You might have some luck in figuring out a trigger, that examines every SAP_CCMSJOB failure and checks if the parent job is a BW chain before sending an alert.
thanks
Nanda