I only ask because it says that the command group push characters out of the 1st rank and into the 2nd where they can do nothing. As lance formations are 3 wide can one with full command take characters?

Read your army book, the pages on lance formation.

I can't actually remember the answer to your question, because I read the book at a mates a while ago, but I remember the answer to your question is there.

Characters must be placed in the front rank (excepting Damsels and Prophetesses) displacing a regular command model as necessary. Standard Bearers and Musicians operate as normal even if not in the front rank.