Here is a way to make that door close if you have a house on piers.
From Lowe's I ordered 3 each Simpson Strong Tie JP44 which I picked up about 4 days later. They cost about $16 each. That picture #3, gray block in which the 4x4 is ensconced cost about $6. Since the 4x4s are only about 14 inches high, I was able to find several short lengths for free. The rest of the stuff I already had.
I was under my house earlier and near where the door in photo #5 was above me. I took my scissor car jack with me and a couple of strong, pedistal serving, broad flat things. I went to the nearest support beam, plopped one of the candidate pedistals under it, and extended the jack to engage the beam. See the piece of 1x4 in pic #4 above the scissor jack. I kept jacking the beam up until my wife yelled through the floor, "The door can finally close!". See pic #5. I measured about 20" from the dirt to the bottom of the newly raised up beam. I did toy with the idea of just stopping here! How much can a car jack cost? Naw. The supports above and below the car jack looked less than ... I don't know... not satisfying.
Here is the non-usual stuff I got my hands on:
h + 6" + 5/8" + 1" = Xh = X - 7 5/8", so my 20" led to me cutting 12 3/8" in length and then drilling 4" deep hole. You could drill 1" in diameter instead of the 7/8" I used. Bigger means you can survive a hole drilled at an angle, but a bigger drill bit is harder to control, and the more wood your cut out, the weaker the support will be.
As I mentioned, I measured poorly and my assembly failed to go under the beam, so I scraped dirt. Ya' know.. its hard to judge levelness when you are lying on your side or stomach. That yellow bar in pic #4 is a level.
I used a 1 1/8" open end wrench to slowly drive the nut down and the top plate up. Hee, hee. The 1st inch was easy! After that it was hard. Finally I was able to jiggle the car jack and it was loose(ish) and I was done. I dragged the car jack, wrench, and level back outside.
That was 6 months ago and the door still closes perfectly.
I don't show it, but I did another jack some 6 feet further one along the beam, because of how much raising via the car jack was needed. So I used this tall, gray block with miscellaneous shims so that all of the support would not be because of just 1 screw jack. It was the lack of a 2nd car jack that made it helpful having that tall block around. I jacked the car jack up until a yell from above alerted me that the door was starting to move. I stopped there, shimmed the tall, block under it and moved to work on the other assembly I have not shown (but is just the same as this one). That is why you see the tall block, and the car jack, and my assembly all in one photo.
Your guess is as good as mine about how much raising by one jack is soooo much that you decide to use multiple screw jacks. But, for about $25 and 1 hour / support, I suggest you splurge.
P.S. my house is a one-story, 1200 sq ft one. Piece of cake.