It looks like a regular 4 inch dryer vent but maybe bent to be more oval.

You can try to squeeze it back to being more round.

If not you would need a round to oval duct adapter.

Yes! That's it! "Round to oval", thank you. Hopefully a quick Google search makes it easy to find.

Nonsense, from what I can see. Get this and a pair of 4" clamps: https://www.homedepot.com/p/Everbilt-4-in-x-2-ft-Semi-Rigid-Aluminum-Dryer-Vent-Duct-with-Collars-MFX42CULXHD/203626510

The large-diameter end clamps onto your dryer's exhaust, the convoluted small-diameter end slips inside that duct elbow sticking out of your wall.

NOTE: this assumes the dryer's exhaust is located close enough to the wall duct, get a longer semi-rigid duct if needed. Just be sure it's convoluted on one end and flat on the other.

@OldSchool88 I think you are right... they seem to have fed me a line and I'm not sure why!