Fogging issue

But the service centre said this issue not all every S26 ultra, they found in some very selective pieces. Different manufacturing lots, specifically.

It's called seasonal issue 😂.. rainy

Thats really sad . I can understand your pain😔

Yes, Its really a worst issue and visiting consumer forum may not give the solution , why I am saying this
First of all : Huge headache
2nd : In India , a court taking any steps for citizens are rare.
Though , I am supporting your effort . I am also just a fellow user of Samsung . You once can try this to remove the fogging issue . I have also tried. It worked
1st : buy some silica gel .
2nd : keep the phone in an air tight box surrounded by these silica gel inside the box with the sim tray open.
3rd : if you have time , keep the box which contains the phone and the silica gel for 2 to 3 days in an isolated place . If you need to solve it immediately , give some or little heat on the box ( not directly on the phone or do not heat it with gas stove or microven , or induction ) with the phone inside . Heat with a hair dryer (best option) for 30 seconds . Then keep the box idle for 1 hour. You will see the fog is not comming any more . Try this once .
Also , I want to say if this trick does not work , try to go to samsung authorised service centre , but tell the service manager not to open the internal of the phone . See, opening the internal of the phone means , the ip rating of a phone will drop . A phone which is factory sealed is the best for its ip rating . If they tell that without opening the phone , the problem has no solution , bring the phone back , try my trick , if it does not work , you should compain to consumer forum . If they also dont take any action , then try my trick several times . I think it will get resolved