According to Oracle's documentation1, the customer options for hosting the Platinum Services Advanced Support Gateway are:
Provide individual x86 64-Bit gateway hardware1
Purchase the recommended x86 64-Bit gateway hardware from Oracle1
Install on Oracle Database Appliance2

The dbmcli -e "LIST IBPORT DETAIL" command is not valid on Exadata X9M. According to the Oracle Exadata Database Machine X9M Implementation Essentials Official Text Book [1][2], this command is only valid on Exadata X3 and X4 models. The other three commands are valid on Exadata X9M.
https://forums.oracle.com/ords/apexds/map/tech/apps-infra/discussion/4342715/monitoring-roce-performance

The two monitoring tools that might be useful in examining I/O performance for the prod database are:
OS I/O metrics using OS tools such as iostat on the database servers.
cellcli (or exacli/exadcli) to examine storage server metrics such as database, category, ceiidisk, and griddisk.
The Oracle Exadata Database Machine X9M Implementation Essentials Official Text Book states that "I/O metrics can be collected from the database server using OS tools such as iostat [1], as well as from the storage servers using cellcli (or exacli/exadcli) to examine storage server metrics such as database, category, ceiidisk, and griddisk". It also suggests using Enterprise Manager host pages for the storage servers to view OS I/O metrics.

https://docs.oracle.com/en/database/oracle/oracle-database/21/ladbi/db-on-exadata.html

Oracle KVM Guest, Oracle Enterprise Manager Agent (OMA), RDBMS instance, Automatic Diagnostic Repository Command Interpreter (ADRCI), CELLCLI, diskmon, and Restart Server (RS) can all run on the database servers. The Cell Server (CELLSRV) and Management Server (MS) can both run on the Exadata storage servers. Specific instructions for installing and configuring these software components can be found in the book and can be referenced here: https://docs.oracle.com/cd/E80920_01/E80920/html/x9m_software_components.html.