It looks like the 35.2 has two floor vents toward the front. These are heat only and the factory is always very sloppy on the crap that ends up in these. The 'duct' is an opening in the floor supports from front to back between the floor you stand on and the ceiling of the basement storage.
Time to remove the grilles and check for the usual sawdust (many threads here) and if there is a blockage. You may need a bore scope but an iPhone can take a pic down under. From what I see they look like a straight shot under the floor to the heater under the bed (how do you stand the noise?). Back at the heater should be a couple of short flex ducts to the floor, remove the flange on the floor and check there also.
Since the return air is under your bed all the air from the vents tries to return back to your bedroom. I would shut off the one that under your bed and let the rest of them push the heat toward the front.
Good luck.
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