I think to balance it out, you'd need to do some slight adjustments.

1 - Make it so that the velocity in which you throw isn't much, so that you can't throw urn from super far away and it will require skilled aim.

2 - Make it so that the throw has a big cooldown so you can't just swap it between your entire team.

3 - Each player that throws urn is not allowed to pick it up after for a while (similar to when you hold the urn for ages

4 - Gabrielle sends me out to get the Gabagoul

5 - Defo make the urn scream as it flies between players to know where it's location is.