That should be:
the so-called 'luck'
But then you can't drop the quote marks and start using the word without quotes. Well, you can sometimes, but you need to know what you are doing. It's tricky. It could result in it looking like you contradicted yourself.
E.g. "I was 'lucky'. So why was I 'lucky'?" is okay. But, "I was 'lucky'. So why was I lucky?" could be seen as an error. Some might disagree with me on this point. I would stick to my guns.
OTOH, "In physics, it is called 'energy'. So where does this energy come from?" is okay. It's tricky. A lot of native speakers can't cope. Some even think "I 'love' grapes", means the same as "I *love* grapes".
Also, "being at the right place at the right time" usually means being lucky, unless you clarify how it isn't. It's an English idiom. So what you say in parentheses undermines the idea that it is only so-called luck and not actual luck. Perhaps you should say "deliberately making sure that I am in the right place at the right time"?
Hope this helps.