Knitting is a technology, and there isn’t evidence it emerged uniformly throughout the world. Think about the environment that Rome is in; what good is something knitted in a hot Mediterranean climate? We have tons of art and literature documenting weaving, which was very important to Romans, but none of knitting. If you have evidence they had it you should publish it.

Knitting is 17th century (in Europe). In Rome you'd have nalbinding as an alternative.

There's a lot of evidence, both direct and indirect, of textile production techniques. I can recommend reading books from Karina Grömer, if you're interested in the subject.

I don't know. I knit a lot. I loom knit too by hand. There are methods for making knitted cords that use nails hammered into a circular wood.

This really looks like it's meant to make gloves and each hole is dedicated to a different finger and a center for sleeves. Maybe it was combined with weaving and there is rope or a wooden hook that we wouldn't see today.

I was going to 3D print one to experiment and see if I could work something out myself.

The fact that there are solid ones really throws me off though. I was dead convinced this was a knitting/weaving tool.