I don't see any issues with this configuration. You could put a second drive on a new disk, or based of your explanation you would be better to assign a single large disk and partition it as both boot and data by a logical partition. Having the large disk with multiple partitions meet your software requirements.
The problem is Tenable Security Center does not allow to specify separated path from the application path during the install (CentOS).
I got the following response from Tenable Support as a work around for this problem:
"You can mount /opt/sc4 elsewhere, but you CANNOT use symbolic links. It will need to be a hardlink so that the host sees the partition or directory as a drive when it boots up."
You can add disks to the CentOS virtual machine through VMWare and mount them accordingly as per Tenable support have suggested. Use the appropriate VMWare datastores to host these drives or, you could use iSCSI to mount volumes directly from the Nimble array and separate the data that way (preferred). Do you anticipate the VM generating a lot of data and having a meaningful impact on the Nimble? If so, separate the data, whereas if its a small appliance chugging along in the background, it may be simpler to just keep it all contained in a single VM.
You might want to check this out for CentOS configuration: