The issue I think, is that keg was sold not being fir for purpose and seller will not accept it. I've bough 2 kegs recently, 1 reconditioned - after seeing how wear out it is, I have bought a brand new one (for mere £20 more).
Is it the usual risk with the cornies?
I've got four, all second hand, three were reconditioned and one not. The one that wasn't reconditioned stank of Fanta, but was fine after a good wash with Oxy and then changing the seals.
I've not had any problems with leaks, apart from when I changed the PRVs for cheap steel ones, which was case in point to never buy cheap PRVs.