Server replication following DC restore

Due to catastrophic OS failure, I had to restore a Server 2003r2 back to my last uncorrupted backup... 7 days ago.

As luck would have it I recently brought up a BDC with 2008r2.

...3 days ago :(

So now my BDC has all the latest info on the state of my domain (they were replicating nicely before poopoo hit the fan), but my DC has NO idea who he is, having just been restored to 4 days before the BDC was born.

They are both now active on the domain, but they aren't talking.

Is the course of wisdom A) blow the baby BDC away and start over, letting the DC think he has the latest stuff (which he will surely pick up eventually anyway, it's only a 50 client domain) or is there a B) option? Some magical way of getting them to be friends again?

I'll probably be here all night setting up the new BDC, but even should that happen and any answers are too late for this fix, I feel like that is something I should know. I just happen to be lucky enough to have a BDC new enough to not have anything substantial on it. What happens in an established domain where the BDC has to do the grunt work until the DC comes back online?

I assume one would not restore their DC further back than the birth of the BDC if one had a choice. Or else force promote the BDC > DC....

Any thoughts?