You will want to search for  (withquotations) "CreateMaintenanceUser" to locate the lines we want to comment.
Example:
"<!--
      <Request Name="CreateMaintenanceUser" EstTime="500" TimeOut="800000" UIName="#CreateMaintainenceProductLogin" ProgressBar="Progress" ActionOnFail="Stop">
        <ConditionTrue>
          <globalSetupType>Primary|DbServer</globalSetupType>
        </ConditionTrue>
        <ConditionFalse>
          <globalSetupType>WebApp</globalSetupType>
        </ConditionFalse>
        <Method>
          <CreateProductLogin Library="Security.Configuration" Class="Security.Configuration.ProductLoginHelper" UIMessageOnFail="#CreateMaintenanceProductLoginFailed">
            <connectionString>@globalConnectionString</connectionString>
            <name>@Custom_DBMaintenanceUsername</name>
            <phrase>@globalBrandSQLPwd</phrase>
            <databaseAuthenticationType>Windows</databaseAuthenticationType>
            <databases>@globalIONDBName/@,ION_Network,ION_SystemLog</databases>
            <roles>Maintenance,db_backupoperator,db_ddladmin</roles>
          </CreateProductLogin>
          <RunExecutable Library="WinUtilities" Class="Installer.InstallTools.WinUtilities" UIMessageOnFail="#CouldnotgrantPermissionstotepo">
            <cmd>cmd.exe</cmd>
            <args>/c echo y| CACLS.exe "@globalDatabaseFolder/@" /T /E /C /G "@Custom_DBMaintenanceUsername/@":W</args>
          </RunExecutable>
          <RunExecutable Library="WinUtilities" Class="Installer.InstallTools.WinUtilities" UIMessageOnFail="#CouldnotgrantPermissionstotepo">
            <cmd>cmd.exe</cmd>
            <args>/c echo y| CACLS.exe "@globalDatabaseFolder/@" /T /E /C /G "@Custom_DBMaintenanceUsername/@":R</args>
          </RunExecutable>
          <AddLSAPrivileges Library="WinUtilities" Class="Installer.InstallTools.WinUtilities" UIMessageOnFail="#Couldnotsetbatchrights">
            <userName>@Custom_DBMaintenanceUsername</userName>
            <privilege>SeBatchLogonRight</privilege>
          </AddLSAPrivileges>
          <AddLSAPrivileges Library="WinUtilities" Class="Installer.InstallTools.WinUtilities" UIMessageOnFail="#Couldnotsetbatchrights">
            <userName>@Custom_DBMaintenanceUsername</userName>
            <privilege>SeDenyInteractiveLogonRight</privilege>
          </AddLSAPrivileges>
        </Method>
      </Request>
-->"
Search for  (withquotations) "CreateApplicationsMaintenanceUser" to locate the lines we want to comment.
EXAMPLE:
"<!--
      <Request Name="CreateApplicationsMaintenanceUser" EstTime="500" TimeOut="800000" UIName="#CreateApplicationsMaintenanceUser" ProgressBar="Animation" ActionOnFail="Stop">
        <ConditionTrue>
          <globalSetupType>Primary|DbServer</globalSetupType>
        </ConditionTrue>
        <ConditionFalse>
          <globalSetupType>WebApp</globalSetupType>
        </ConditionFalse>
        <Method>
          <CreateProductLogin Library="Security.Configuration" Class="Security.Configuration.ProductLoginHelper" UIMessageOnFail="#CreateMaintenanceProductLoginFailed">
            <connectionString>@globalConnectionString</connectionString>
            <name>@Custom_DBMaintenanceUsername</name>
            <phrase>@globalBrandSQLPwd</phrase>
            <databaseAuthenticationType>Windows</databaseAuthenticationType>
            <databases>ApplicationModules</databases>
            <roles>Maintenance,db_backupoperator,db_ddladmin</roles>
          </CreateProductLogin>
        </Method>
      </Request>
-->"
Click SaveAs and change the name to EverythingElse.broker.xml.  Ensure you save in the original location.  \Setup\BrokerFragments\