Working with my church sewing group, we use crochet thread on the Lutheran World Relief quilts. I have brought a small pair of pliers to use to pull the needle through on occasion. Then a lady in our church who runs an embroidery shop gave us chenille needles, and it has made all of the difference in the world. They come in different sizes, but the eyes are easier to thread, and the needles are strong.
Here is what LWR says in their instructions about ties: Crochet cord or embroidery floss is easier and sturdier
for tying. You may use yarn, but pay attention to the quality to ensure a sturdy quilt.