To mount an external drive with LVM called VolGroup00, you will need to rename it first, since the current host already has a LVM named VolGroup00
With the drive mounted using an external drive caddy.
List the LVM's with the UUID
Rename the volume name to another name like 'VolGroup01'
/usr/sbin/vgrename <UUID> VolGroup01
Activate the LVM's
/usr/sbin/vgchange -a y VolGroup00 /usr/sbin/vgchange -a y VolGroup01
Scan for Logical volumes
Create temporary mount point
Mount the Logical Volume that has the files you're after
mount /dev/VolGroup01/LogVol00 /tmp/mnt/
Scan all disks for physical volumes