Because Placker needs authorization to publish comments or changes under the name of another user, it is required that this user creates an account at Placker.com, otherwise comments will be assigned to the user that holds the Trello sync token (usually who imported the board).
A common solution in these cases is to ask team members to create an account at Placker.com linked to the Trello account, even if you are not going to add this member to your Placker subscription later.
In case you like to make it very clear which changes are triggered by Placker, the best way is to introduce a ‘Placker user’. This user can be added to your Trello boards and set as the user who manages the synchronization and updates between Placker and Trello. This way it is very clear to everyone that this change originates from Placker. Learn more about this in this article.