RD Gateway with cached credentials

We're using a RD Gateway server and a RDS Host on a remote site. Both of them

are joined to the internal domain. There's no DC on this remote site (VPN connection to

the main site where AD DC are located).

Connections are made using domain users accounts.

My problem: if the VPN is down, RD connections are refused by the RD Gateway.

Is there any way to allow the RDGateway to authenticate domain users using local cached credentials ?

(with domain users profiles created locally)

Thanks,

Vincent