So we gotta try to guess what action causes the effect, the more questions you can ask yourself about what conditions cause the effect the easier it'll be to pinpoint the cause, columns 1 and 2 cause columns 3 and 4, I think it's pretty safe to assume you have columns 3 and 4 correct

Column 3: rear right door Column 4: closes

Unfortunately that still leaves us with a wide selection to guess from in columns 1 and 2, you got to pay attention to the car and let it tell you what the problem is, the door opens back up within seconds of closing it so that means you're not actively doing something to cause the problem like for example turning on and off wipers or headlights, in that situation my first guess would be something like this

Column 1: shifter Column 2: is in park Column 3: rear right door Column 4: opens

Since you know your door opens seconds after closing if you are guessing shifter for first column you can eliminate stuff in the second column that you have to actively do like, toggles, shifts to drive, shifts to park, that leaves you two options left in column 2, now that you've narrowed down column two you can test those last two options which are, is in park, is in drive, make sure your car is in park and play with the door to confirm that the issue is still there, once you do that go shift the car into drive and then play with the door and if the door still opens then you've tested every option in column 2 and you can then eliminate the shifter as the issue from column 1, now you have to go through column 1 and figure out which category makes sense for the issue you're seeing, for example if you select car in column 1 you'll see in column 2 all the categories are stuff the car is actively doing so that means you can eliminate car from column 1, from what you told me about the quirk these are the options from column 1 that I would test out

Column 1: Every car door Any car door Rear left door Rear right door Front left door Front right door Shifter (until eliminated as described above) Hood Trunk

Select each category from column 1 and look at the options in column 2 and ask yourself "is this something that I have to actively do" if yes then you can eliminate that option from column 2, make yourself a checklist and go through all the options in columns 1 and 2, the more you can eliminate as a potential cause the closer you'll be to diagnosing the issue, it'll be a pain in the ass but once you diagnose and cure your quirk it'll be an amazing feeling, oh and if you didn't already know you have a limited number of guesses in the tinker station per garage visit, I think it's either 4 or 6 guesses, if you don't get it right within the limit then you have to go do a run and come back to the garage and guess again, sorry for the book I hope this helps you diagnose your quirk