Resolution:
No, you can't. If you take a look at the BWFB documentation -> User Guide -> Chpater 7 Deploying Formflow Applications -> Running a Servlet Engine -> Running
Tomcat:
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Note that standalone FB deployment does not have the concept of development or production mode.
It is a PS5-based deployment that put all TIBCO libraries under Tomcat/shared/lib.
For this reason, BW instances underneath FB might conflict (perhaps some other issues too), hence this limitation of having only one FB application per Tomcat instance.
So two FB applications cannot have the same Tomcat Shared classloader.
In that case the workaround is probably to register Tomcat to the TIBCO domain twice with different server.xml (different port) and deploy on each one.
The Apache Tomcat software used for TIBCO BusinessWorks FormBuilder can host only one TIBCO BusinessWorks FormBuilder application. Therefore, you cannot have any of the following:
*    More than one TIBCO BusinessWorks FormBuilder application
deployed on one Tomcat servlet engine instance.
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