You probably are correct - C. trifasciata subversa, but we have to make sure the suture line is not dark, especially apically (perhaps lighten the other image a bit?). And I'm a bit struck by how deeply the lateral pale area penetrates toward the basal angles (which is characteristic of dark-sutured species in the northwest). Perhaps it's just the tucked position this one appears to be in. The "band" between the eyes is just a bit broken medially (not two "well separated"(1) spots). But Gordon's key states that can rarely happen for females of C. t. subversa (and this is a female by the black head).

PS: Any idea what its eating?

I saved the other image and adjusted the levels in photoshop there is no darkness in the center. No pronounced line at all. I do not have editor privelages or I would replace the photo with it adjusted. Hope this will help.

...is never going to eclose, that's for sure. Perhaps something lepidopteran, it has the spun-silk look of a moth cocoon.

Lady beetle larvae sometimes feed on moth and butterfly pupae. This one chewed through a silk cocoon and used its forelegs to pull the pupa towards it: