The statue of limitations is 10 years, so it's moot at this point and has been for a while.
I believe there was an investigation several years ago. However, the IOC/FIG have been very clear that they will only convict of age falsification if different dates of birth are submitted on different forms used for international competition. For example, Kim Gwang Suk and Hong Su Jong had multiple different dates of births submitted for international competition.
This is most easily seen with Dong Fangxiao and Yang Yun. Yang Yun publicly stated within the statue of limitations that she was underage in 2000. However, no action was taken because that younger age was never claimed on official paperwork. Dong Fangxiao, however, actually submitted her true birthday (which showed she was underage) on IOC paperwork when she was certified as an official at the 2008 Olympics. The fact she put it on official paperwork within the statute of limitations is what led to the 1999 and 2000 teams being stripped of their medals.
Basically, the organizations are going to accept whatever the governments tell them unless the governments submit multiple birth years to the organization, making it impossible to ignore, or the athlete uses multiple birthdates with the organization in other areas.
And once the statue of limitations is up, athletes can offer the truth if they want to with no fear of official reprecussions.