Ok, I have an idea, but I haven't researched this thoroughly.
What if you created a new test save in Sunset Valley and Installed Nraas Traveller, copied the problematic world .NHD and .Package files from the original save folder to the Sunset Valley test save folder, have your sims travel there(to your original corrupted save file's world) and do the following:
Traveling to a custom world destination is essentially the same as traveling to China, France, or Egypt.
You will be asked where you'd like to stay upon arrival. This choice includes empty residential lots (which you will not be charged for) and base camps in the world (which you can add if you like). The selection system uses the University interface if you have that pack installed so do not be alarmed if you are asked "Where would you like to stay this term?" The mod knows you are not in Uni World and will react to your choice appropriately.
By default, your stay will be timed, and your family will automatically return home once the travel clock is full.
You can pause the travel clock at any time using the mod's "Pause Travel" option.
Also, if you wish to turn off the vacation restrictions, you can disable the "Treat as Vacation" option.
Doing so makes the game think you are in a hometown, allowing you to go to work/school, or do things that are not normally available in Vacation worlds.
Note though, that you are still technically on vacation. No one at home will age, and you can still complete your vacation at any time by switching the "Treat as Vacation" back on, and traveling home.
And maybe after following the above instruction you can switch to your original corrupted household family and play normally.
as I said I haven't tried this, just something that crossed my mind.
