$jobs = Get-VBRJob | Where-Object {$_.TypeToString -like "Vmware*"} #for VMware, you can remove the pipe to Where-Object to get all supported jobs
$jOpts = Get-VBRJobOptions -Job $jobs
$jOpts.BackupStorageOptions.RetainDaysToKeep
This will reflect the simple retention restore points, GFS is stored under the GenerationPolicy property of $jOpts.
But basically everything you need to check / set is under BackupStorageOptions returned by Get-VBRJobOptions.