Aw thank you. If only love could cure them!!!
Yes I agree with you it looks like lash 

Do you still have that piece of lash material? If you do, I would cut it open to confirm lash, although it certainly looks like it anyway. Inside it normally looks kind of fibrous.
To cut her feathers if she is not very compliant.. you can wrap a towel around her and lie her on her side, cover her head lightly with something (this quietens them right down and they stop fighting) then you can concentrate on cutting those feathers.
I normally will hold the chicken kinda like a football under one arm, but with them facing behind me so I can cut the feathers with my other hand, but this chicken in particular is really quiet and just waits for me to finish, she's a darling. The towel works great for others if there is no one to help out.
Some people have said they have cured chickens with salpingitis, but it is imperative to catch the infection early. So I think it would be at least worth giving antibiotics a try. When they pass some lash material they will have a huge sense of relief so she may be a lot better in herself now for a while anyway..
Oh yes, I also get laughed at for tucking them in