There is a possibility you could re-start your server and the "spawn on death" values in your SQL be on, as the named mobs were not killed. Since the named mobs would not be there on restart, and the flags still on, they would never spawn again until the flags are properly set. I made these flags so as to insure the rarity of the mob; there will never be more than one instance of the same mob at a time.
Here's a solution I am using, that will insure the values are right at start up -
place this sql file file in your c:\mysgl\bin\ directory (or where ever your sql bin dir is) ;
http://www.nahunta.org/~angelox/files/SetValues.sql
Then, you need to alter your eqemu "start.bat" file and add these lines at the top;
echo resetting global values ...
C:\mysql\bin\mysql.exe < C:\mysql\bin\SetValues.sql
sleep 2
echo done.
or, if your eqemu directory is in the same place mine is (as per 7.0 install), you can use mine;
http://www.nahunta.org/~angelox/files/start.bat