So, the point of an inciting incident is that it forces change upon the life of the protagonist. In fact, that is the literal definition of an inciting incident - if the protagonist is not forced to react to it, it is not an inciting incident.
What this means is that what comes after the incident is infinitely more important than what comes before it. There is nothing wrong with an inciting incident being something random or coming out of nowhere. What matters is that the protagonist then has to react to it, in turn setting in motion the events of your story.
If your inciting incident is not the first thing that happens in your story, then what becomes important is establishing your protagonist in such a way that their reaction to the inciting incident when it does occur is in character for them. Again, though, the incident itself does not need to be even hinted at prior to taking place. You can foreshadow it if you really want, but that's not what's important. What is important is that it impacts the life of your protagonist, and that it causes change.
A while back I wrote a quick guide about this that you can find here: https://tapas.io/episode/2600801
I would also strongly suggest getting your hands on Story: Substance, Structure, Style, and the Principles of Screenwriting, by Robert McKee - it is very helpful with things like this, and I'm still kicking myself for not getting my hands on it years ago.