How do I map 2 services that are marshalled and unmarshalled differently using one single routebuilder?

I have 2 services( For now, lets assume service A and B). Service A uses legacy code and is marshalled and unmarshalled differently in the processor. Service B uses the latest code(JaxB Binding) and is marshalled differently. Currently, I have written a Routebuilder that maps to the appropriate service based on the header(using choice operation: if header=X, map to processor A). However, Service A still uses old processors to perform the marshalling and unmarshalling. Is there a way to tell camel to route to a particular service based on how the service is marshalled or unmarshalled. If you need more clarifications, please let me know.

Thanks, Gautham