To me it sounds like what you're looking for is some way to do failover of VPN connections, and at the moment you are just relying on a single VPN adapter being already taken to prevent 2 simultaneous connections. You are relying on an error state to achieve something, and that is very brittle design.
As a suggestion, you could perhaps write a simple batch script that starts the openvpn client and then polls regularly over the connection if resources can be reached. Then if it fails repeatedly at that, you could try first a remedy step to simply restart the connection. If that also doesn't work, then have it stop the first connection and start the second connection. And to round it off, do an occasional recheck if the primary connection is available again. Bonus here is that the failover works fully automatically.
But yeah I don't think your reliance on an error state is a good thing. Basically, there was a problem, now it's fixed, but you happened to rely on it being 'broken'. That's not a good motivation, in my personal opinion.
