For sure if you've got the rudders turned at 45 degrees, they're going to stall. Even EPO's won't tolerate that angle of attack
But what it sounds like is that you stalled the leeward hull. Don't forget that you've got no daggerboards, so keeping the flow attached to the hull is pretty important.
The only cure for stalled hulls is to ease the main (not the jib) to help the boat bear off, get going again, then power back up. Try to use the sails to help steer the boat.
This especially important in flat water (Austin Lake) when you've got your weight way forward and the rudders are lifting out.
How far were you travelled off? (Main and jib?) What was your total crew weight?