Getting strong rope wound up being surprisingly easy. Maybe the training room stocked it so Tributes could practice knots and such for survival purposes. Whatever the reason, Joan was able to procure some and bring it back to her room. Binding R was also easier that she expected. Sherlock had taught her a number of knots, and taught her which ones were easy to get out of and which would hold even the most aggressive suspect. She was pleased that she remembered those knots, and was able to secure R in a chair in her room.
Time skip!
Now all they have to do is wait.