The last character of the model number is a zero, not letter O.
FGHD2433KW0

That's the left side of the frame. The fill flume is on that side of the tub. Could be a slight leak from the hose on it.

The flume also acts as an air gap for the water inlet stream. If you have hard water, accumulation of mineral deposit can cause the water stream to splash askew.

You can find parts diagrams on several online vendor sites.

The first picture I posted is of the right side of the dishwasher when I'm standing in front of it. The picture I'm posting here now is of the left side, nearest the sink, with no corrosion. The brass piece showing is the flume, I presume? We do have a water softener.

I see. Your close-up picture wasn't clear which side. I don't have a conjecture at the moment on what would cause rusting/corrosion on the right side.

That's the water inlet valve in your left-side picture. The fill flume is further up on the side of the tub. A hose runs from the valve to the flume. But anyway, there's no problem on the left side.

What a tech will do is carefully remove the D/W and look at the side searching for water trails. These are usually seen as calcium or detergent streaks running down the sde.

Another trick is to take some baby power blow a little dusting of powder under the d/w on the side you suspect the leak and then check the d/w after each cycle to see if the powder is wet or disturbed.

If I am not wrong that model uses a fan to dry--it is mounted to the tub top. Is the vent toward the bottom of the door anywhere? I forget where these vent out. Maybe blowing damp air into that one area? You may want to feel under there during the drying cycle.

I noticed something new today. There was a quarter-sized whitish drip spot on the laminate floor near the corner of the door this morning. When I wiped it off, I noticed the bevel between the two laminate boards is darker in color, as if water sat there for awhile. (This is the area I circled on the picture. I had already wiped the white spot off the floor.) It's looking more like a leak in the door, or the gasket. Or perhaps it was another one of those times where one of us turned a glass upside down and splashed some water out of the tub, or some water splashed out when we were unloading. If there were enough of these kind of splashes, settling into that bevel, maybe it could work it's way down deep into the flooring and cause the puffing?