You cannot resurrect summons by their CHARACTER_xyz name, because such name does not exist at compile time, that is true.
However consider the following code:
IF
CharacterDied(_Summon)
THEN
CharacterResurrect(_Summon)
This will resurrect summons too.
have you experimented with spawncharacter(template)?
Maybe if characterdied then getcharactertemplate and spawn that one. Don't know if thats possible though
SpawnCharacter is a charscript/itemscript-only function though, you cannot use that in story scripts.