It is possible, but it's extremely difficult.You'll need different skills depending on which Antediluvian you kill, and even then you still have a chance of failure. It took me tens of events before I could kill Absimilard.

Save scumming doesn't work in a game with fixed seeds like CK3. Unless you save scum way before the fact (at least a month before the start of the hunt) or you change the odds by changing your stats asked in the event.
If you just try to save scum something like a day before the event and don't change anything, you could save scum for years without a result.

Get the advanced cheat menu and give yourself 100 in all stats. Than revert back to normal. This will gurantee you get past everything. Pick troille since that is the easiest.