A third option always ends up being spoiler with the way the system is designed. We desperately need ranked choice voting in this country - otherwise there will never be a third option. Until then, there will only be bad, worse, or not voting for bad, which ends up being a vote for worse.
I'd say this even if the third party candidate were the child of Bernie Sanders and Jesus - the system is designed for power sharing between two political parties - there's no room for a third without a major overhaul.