Sadly 8.8 is the minimum supported version of VSE in ePO 5.1
You might be able to check in the install package but the management and reporting extensions as unsupported.
Cheers for that, I thought so.
If I transfer a v8.7 system v4.5 to 5.1 and I know it cannot be supported with policies and client tasks. will it keep it's existing policies and client tasks locally e.g. daily scans and policies so given me time to update the software to 8.8 once on the new ePO, or will I need to upgrade it first before transfering across to 5.1