Yes, that looks like the vent for the front diff.
One end of it is supposed to be open like that.
The other end goes to a nipple on the top of your front diff.
It's designed to allow you to ride in deep water without getting any in your diff.
That hose is supposed to go up behind your radiator and end up in the area that is accessible by removing the access panel in the bottom of your front storage compartment.
You can see it on the far left of this photo I took earlier (ignore the red circles).
If you have any trouble feeding it back up, you could feed a coat hanger down from the top, tape that tube to it, and pull it back up, then zip tie it in place up there (don't crimp the tube).
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