If it's a one-time $100k you can just slowly withdraw small portions of it and probably nobody would notice. It depends how much you're trying to launder.
You really think that alerts in banks are that stupid? It doesn't matter if you are sending 100k at once or below some treshold. It will get alerted and spotted anyway. You just need to make transaction look plausible.
I have transferred tons of stuff to my bank over the years (all legal), none of it ever got "alerted" or something I had to describe.