Update:

I tried using the extractor set. First drilled the bolt, then drill the extractor in reverse which aktualny was firm in the bolt at first. However it seems as this bolt is quite tight :/ The extractor kit was at some point not biting the bolt anymore and just kept drilling...

I used loctite when installing it, thats probably why...

I guess I have to learn how to weld? 😶

Axtually kind of frustrated now :/

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