The ... passed to LogEvent denotes a variable number of arguments
local a, b, c, d = ... retrieves the first 4 arguments from ...
local a = ... retrieves only the first etc.
local text, playerName, etc = ... above is all the arguments passed to LogEvent (from the CHAT_MST_LOOT etc. events from the OnEvent ... payload)
Saved Variables can save as many (or as few) pieces of information as you need. The text layout will (in most cases) be representative of a lua table as that’s the most flexible form to save in. See:
https://warcraft.wiki.gg/wiki/Saving_variables_between_game_sessions