Contract investigator here. Don’t rule out the immersion school based on the advice here, which can be… how to put it politely… “variable” in quality. The default answer is that you should not leave the country. Ever. That makes for easier investigations but it also makes for job candidates with poor language skills and limited world experiences.
I’ve benefitted enormously from working and traveling abroad. You almost certainly would too, especially if it gets your skills in a high demand language to the next level. The benefit would outweigh the additional work that a notional future investigation would involve. Advice: talk to a recruiter at an agency that you’re considering applying at one day. Don’t go fishing for his blessing, but ask him the same question you asked here: will it preclude high-level employment down the line? I’d be surprised if he said yes. Most agencies hiring candidates with key language skills want analysts that have been to the Maidan, not analysts who read about it on reddit.