The move from ITRM 2.7 on 9.1.3 to ITRM 3.9 on 9.4 is a significant one, and involves a fair amount of architectural change. If you haven't already, you'll need to do a brand new SDW-based planned deployment of ITRM 3.9, and then migrate to it.
See the ITRM 3.9 Migration Guide for a complete understanding of the process to migrate this solution. As mentioned, the first step is to install and configure a separate ITRM instance. Note that post ITRM 2.7 the installation and configuration of the ITRM solution is very different that older SAS installations and this process is referred to as planned installation. Information about planned installations can be found on the SAS Install Center (look under the SAS 9.4 banner and choose the operating system on which SAS is to be installed.) On these pages, review the information about Planning Order Installation and Configuration Instructions (for Unix and Windows) or Users with Planned deployments for z/OS. Once ITRM 3.9 is installed, see Chapter 4 (Migrating SAS IT Resource Management 2.6 and 2.7 PDBs to IT Data Marts) of the ITRM 3.9 Migration Guide to understand how to migrate the ITRM 2.7 PDBs to ITRM 3.x IT Data Marts.
If you have questions/issues with any of the above, please feel free to contact Technical Support.