Welcome in H.C.M.
I have gone through your query regarding surgery of rupturred ear drum. As you said that your mother is having only one working ear and unfortunately that had become diseased now due to accidental rupture of ear drum and than after repeated infection in that particular ear.
One symptom of medical history is very important that your mother is now can't hear by hearing aid
, this indicates some bad development I.e. now sensory neural deafness
is adding on with previous conductive deafness. This sensory neural deafness can't be corrected by ordinary ear surgery of middle ear and ear drum. This may be the possible reasion that your surgeon's are not doing ear surgery.
Your mother may use digital hearing aid or if your ENT doctor agrees than cochlear implant
may be tried for improvement of hearing.