I do think she was shamed when you brought her to the restroom - and perhaps on other occasions. Our natural response to shame is to retreat, to put a wall, and to feel that we are defective. I think that your daughter reacted as any one would when you confronted her about her hygiene. That being said, let's look at some solutions.
A new, radically different approach is needed her. First, your daughter needs to know - rock solid - that you love and care for her. I encourage you to apologize for the restroom incident and for any others that may have left her feeling uncomfortable,embarrassed, shame, and not loved.
Then...set about making things better. My suggestion is that you take your daughter to the local hairdressing salon or spa. Give her the full treatment - nails, hair, facial...the works! Let her - and you too - be pampered. This should be a "girly" day of relaxation and fun. The hairdresser/massage therapist (whomever) will be teaching her about hygiene - right!!! That get's you out of being the tough disciplinarian whose is checking her panties, her hair, her skin - right!!! At the end of the day...you can have a little chat about how good it is to keep your skin clean, etc. and what she can do to keep this up. Get her the necessary products for someone her age.
At 10 your daughter IS changing. You mention her weight, but you don't mention height. Has she also grown taller? If she hasn't, she likely soon will add some inches to her frame.
In my experience, 10 year old girls really don't understand hygiene all that well. They need to learn what products to use, and so forth. But they need to learn these things in ways that do not damage their self-image and self-esteem.
A day at the spa will give her the sense that you care about her and want her to be happy. And truly that is what you want.
Let me know how you feel about my answer.