Legal Resident of foreign country

I was received a tentative offer for a position in DC, and submitted all of the required paperwork for the suitability (Background) investigation. I just heard back today that the offer was rescinded based on the fact that I was living in Japan as a legal alien (on a spouse visa) for an extended period of time (6 years). They said that their security department has limited resources to conduct an investigation in Japan and that they only do it for Military or DoD government employees.

My question(s): Is there any way to mitigate this? Is this going to be a common response for other agencies as well?

I asked the agency if there was anyway to mitigate this and their response was basically, they were incapable of interviewing foreign nationals. This to me would imply that if I lived in any foreign country in say the last 10 years…that I would be ineligible. Yet, I have not found anything, even under the foreign preference adjudication that indicates living in a foreign country for an extended period of time would be an issue…granted I get why many would think that there might be a preference, but it is something I feel could be mitigated based on the evidence and circumstance.

There are thousands of U.S. citizens living abroad for various reasons; work, school, spouse is working overseas, etc…, so that in and of itself is no reason to deny you an opportunity for a job. Background investigations on service members who live over seas happen all the time, so that is not the issue. Sounds to me like the employer used an easy out to not have to go through this process.