Layer 2 VPN vs Layer 3 VPN

Good morning TK_Liew

I was planning to put a Balance 710 in the HQ and then Balance 380’s for the regional office/various counties (about 7); furthermore remote in country users will be connecting via MAx BR1 routers (3G + Satellite) to the regional, in country, Balance 380 offices. The multicasting is required for voice PTT

Based on your comments, who will handle Layer 3 routing? Do you recommend installing an additional Peplink in the HQ?
Will this be a scenario of Star/Mesh Topology?

Thank u