I spent a day making lobster stock just less than 2 weeks ago. I had some things come up and ended up forgetting to freeze it, though it has been in my fridge the entire time.
Throw it out or boil it and freeze it?
I wouldn't toss it. As long as it was cooled prior to being placed in the fridge I would simply freeze it. Making it pasteurized it in the first place. Chances of bacterial outgrowth at fridge temps are vanishingly small, and as it's likely to be boiled when next used...well, there you go.