Mark hit it on the head...
I suspect that your condensation is residual from your leaks. We have a '94 tri-axle Ltd, and there is a LOT of stuff that will hold water for a very long time. If your leak was in the ceiling, around the A/C or a vent, for example, it could have run down the inside walls through the insulation. The insulation could still be saturated. Then, there's the lovely 'carpet' on the walls that can also hold water, and hold it in. Your plywood floor sounds like it was probably saturated. The insulation under the floor is held in by the belly pan.
It may take a long time for all of that moisture to dry out. My suggestion would be to store it with the vents open and to have the windows open on the trailer as often as possible for as long as possible each time. Eventually, it will dry out.
Best of luck on this one!
AIR 2053 Current: 2006 Born Free 32 RQ Kodiak Chassis, & 1995 Coachmen B-van
Former Airstreams: 1953 Flying Cloud, 1957 Overlander, 1961 Bambi, 1970 Safari Special, 1978 Argosy Minuet, 1985 325 Moho, 1994 Limited 34' Two-door, 1994 B190 "B-Van"