I am currently running CA Dispatch 11.6 with an interface to CICS 5.4 installed. Is step 13a required for the 11.7 install or am I good as-is?
Your Dispatch 11.7 load library does not know that you have the CICS interface installed. It does not contain the CADSINTC and VCICICS modules that you need to support the interface.
If you are going to be accessing Dispatch 11.7 via CICS then yes, you will need to run step 13a.
Before running DSINCI1, make sure you have apar SO06882 applied. This apar replaced the DSINCI1 member to prevent ASRA abends in CICS.