To send someone to jail for five years for (essentially) saying
"I think that I'm allowed to vote, but my name is not on the voter's list, so I want to fill in a ballot before the polls close, have you determine if I am allowed to actually cast that ballot later, and if you determine if I am actually allowed to vote to count my vote but if you determine that I am not actually allowed to vote to destroy the ballot unopened."
is just a bit much as it would mean that EVERYONE who casts a "Provisional Ballot" is risking incarceration should it later be determined that they were ineligible to vote.
Essentially this woman was sent to jail for five years for APPLYING TO vote, since her ballot was destroyed unopened.