Targa Rally/Autosolo K11 Micra MOT failure replacing ball joints

My K11 Micra has been sitting for a year. Now lock down has eased time to MOT it which it failed on a ball joint.

[@user-dh3ml4ql2b]

heating the metal is not advisable, it will make the steel brittle

[@Holms]

Ball joint which you have doesn't even get into hole from the start.. ball joint i have goes through the hole freely, I don't even know what to press in there... and the ball which I've pressed out now goes freely too. In such cases I'm totally clueless what to do next..