From the looks of the video I could tell that the gas\air mixture did not seem right. I was going to suggest a complete teardown & reassembly of the burner tube. Adjusting the spark/flame sensor as well.
I'd replace the little tube you slide back & fourth to adjust the air mixture, it's looking quite rusty.
Down the road you might want to think about installing a hotrod so you can run your heater off of electric when you have full hookups.
I just added a hotrod to my Atwood HWH. Wish I had done it 5 years ago!
Oh, You might want to check your fridge burner as well.
RM