DCI interconnect (2DCs) with stretched L2 - Routing

We are planning to expand with a second Datacenter. There is a wish from our server team, to do L2 DCI (VXLAN in both DCs) due to easier transition in a disaster recovery situation. (and to be able to have active-active services)

We have every sites connected to our HQ via MPLS (Single Multihomed). Til now, every site has its own prefixes for routing, which makes it easy.

With the second DC, (and partialy same Subnets), we would have to route the same prefix to both sites.

This would work, but in case of loss of the crossconnects (2x10G) we would have a split-brain situation.

--- RT1------# HQ #------RT2--------- | | @@@@@@@@@@@@@@@@@@@@@@@@@@ MPLS @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ | | | | | | | | -----------# DC1 #---------- <-- 2x 10G LACP L2 --> --------- # DC2 # -------- RT1 RT2 | | RT1 RT2 10.10.10.100/24 | | 10.10.10.200/24 10.10.10.0/24 | | 10.10.10.0/24 | 

What would be best solution here? How could we route the same Subnet to both locations, but have no issues with Split-Brain?