Well that might be the case now. It wasn't the case in recent decades. Lots of states didn't cross-reference death certificates to birth certificates. Probably with all the money spent by the NSA after 9/11, that hole is starting to be plugged. The move to requiring REAL ID Act of 2005 compliant ID's for travel on aircraft and other activities has prompted many states to upgrade the integrity of their vital records. Read my previous post in this thread.
Interesting “day we got married story”. I wonder if these people getting uncovered is from the real ID or just bad luck.