If I understand you question correctly, you can do the following:
- have a VM (i.e. Windows or Linux)
- attach Symmetrix Gatekeepers to this VM as Raw Device Mappings (best is if you put them on a different scsi bus), ofcourse you have to map & mask your gatekeepers to your VMware environment first.
- install Solutions Enabler on this VM
- install rpowermt tools on this VM
This way you can use also ESXi. Also you do not need a dedicated ESX host for this VM.
By using raw device mapping for your gatekeepers, Solutions Enabler can issue commands across the gatekeepers even while it is a VM. This way you can also run other Symmetrix software, such as SMC in a VM.