AM currently does not support Amazon RDS for Oracle. RDS has its own way to control privileges through its own packages not provided by Oracle. The current AM installation will not work as it rely on Oracle SYS account and grant needed privileges from there.
The grants needed are listed in sql/sysdba.sql file.
If you really want to try, you can export a working AM instance from regular Oracle installation with privileges to import into RDS Oracle instance, to skip the grants. We have not attempted that yet.
Notice that OAE (Oracle Application Extension) will also not work on RDS.
If we were to do it in the future, we could create a role and grant all needed privileges to it as a separate step, ahead of installation and grant the role with RDS packages to the AM user.
Please raise an Idea via our Ideation on Broadcom communities at the link below: