Being on the ground level might spell some serious problems down the road if there is ever a backup in your building.
It sounds like water pressure is non-existant along with a slow moving drain.
Pulling the toilet and running a large snake into that drain will cover basis on the event of removing the clog if one exists.
You might want to consult with them again and if they don’t consider this….it would be prudent to move if the situation gets out of hand.
More than likely it was like that before you arrived and worked in this fashion without error/backup.