My husband has been off his supplements and B12 for 2 weeks. What is the best way to restart the supplements? Where we left off or introduce a little slower?

You can just try restarting where you left off.  

If he experiences reactions at the higher dosages, then you’ll want to back down to a lower dosage.  

But if he’s been off them for just 2 weeks, he likely won’t have any issue restarting them again where you left off.