Afaik bringing extra guests is only possible in the AMS/CDG lounges by the way, not in other Skyteam lounges around the globe.

I found the rules to be vague as well. See my post here for more: http://www.flyertalk.com/forum/13527748-post7.html

I guess that Swapping your BP should no problem, altho that would be a last resort. You should all be able to get access.