Try to follow the leak back to its point of origin. That floor probably has a slight pitch towards the stern. You may be looking for skinny and only a slightly damp trail as it won't accumulate until it hits that wall. My first thought would be an overflow from the drip pan. It could travel 'downhill' behind furnature until it gets to that wall where it will spread out. Check the drip pan drain. A second thought would be a leak or condensation on the hose feeding the unit depending on where the pickup is, but you should be able to quickly tell if it's salt water, and that hose is not likely to develope condensation. My 3rd thought would be condensation at or near the vent or along the duct if you leave it running on a/c while away instead of switching it to dehumidifier. Miami is hot and humid, and that ductwork could get real cold trying to keep up.
It would not be from a clogged strainer as that would shut the unit or give you a code (I believe P5), also the discharge would be reduced.
Another possibility, although having nothing to do with the a/c, is a leak in a water line, connection or the waterpump or actuator. Any of that near the location of origin?