I'd recommend opening a service request with EMC to see if this is a bug. I have seen issues when using the Wizard and trying to force it to use a pre-configured RLP Raid Group.  I think you can still use the manual method and then be able to select a pre-configured raid group for RLP.  glen
I've just came across a mirrorview A wizard configuration that created a pool on 3 different disk types using all of the hot spares, even though we had a dedicated traditional RAID group (not on vault drives) to use for RLP. Looking at the Mirrorview Wizard rules don't think the wizard can avoid doing this on VNX2 where hot spares are not configured. • By default, the system configures reserved LUNs as thick LUNs using the following method: 1. It configures thick LUNs in pools that do not contain server-visible LUNs or mirror images and contain the least number of reserved LUNs. 2. If the conditions in step 1 cannot be met, the system tries to create a new storage pool (three- or five-disk RAID 5 or two-disk RAID 1/0) for the thick LUNs. It then configures the reserved LUNs on this pool. 3. If no disks are available to create a new storage pool, it places the reserved LUNs in an existing pool that has enough capacity. 4. If there is not an existing pool with enough capacity, it evaluates RAID groups using steps 1 to 4. 5. If it cannot find an acceptable RAID group, the process fails.  The wizard seems to be at odds with hot spares on VNX2
VNX2 Mirrorview/A wizard query