The "trick" is getting the Q permit from PP without actually going to Prairie Portage.  The only alternative I can think of is to send one or more of your party up there via a tow to pick up and pay for the Q permit and then back to US mainland to start out elsewhere (everyone still needs an RABC).  Last time I went into Q ( 3 summers ago) they offered to sell me an RABC on the spot, rather than having to order it through the mail.  I assume they still do that  :-/  To answer your camping question...yes, as long as you stay off-shore you can paddle both sides of border with an RABC.  Not sure how that relates to being able to fish Canadian waters...I do not fish.
You are correct that wind could strand a canoe party but with a cockpit cover kayaking is not an issue in the wind, just more work if you are heading into it.