I presume you have visited/toured this facility. Have you been able to glance into other residents' rooms? Were there a lot of personal or 'seemingly' precious possession visible? Does this facility have a Facebook/webpage presence with resident/family comments?
I guess it really comes back to how disappointed would your mother be if the quilt did not go with her. A compromise might be seeing how the first month or so goes. It could always make an appearance later.