I've never set it up with a virt. link-local address. In my setup, I use a 'real' v6 IP
configure vrrp vlan my-vlan vrid 30 add aaaa:bbbb:cccc:dddd::3456
Have you tried that yet, or would that break things?
Frank (readily admitting that link-local is just a magic black box to me, so I avoid it)