haven't read all of previous posts, looks like a lot of ranting.
I do sympathise with the OP – I have had a bad case of tyres not suiting the car, but before replacing them I tried everything to make them work, pressures, suspension getting checked out, camber, tracking, swapping wheels etc. But at the end of the day when the tyres were changed it was fixed.
As for not being able to spin whilst normal driving that is tosh. Touch wood hundreds of thousands of miles, 28 yrs of driving and not an accident I hit diesel on a wet road on a motorway slip road and I was out of control.
Bite the bullet and replace the tyres if you have a family spend a few hundred quid and the garage will surely do a deal.