As your child is having high TSH and low T4 it is suggestive of Hypothyroidism .
The patchy baldness on her scalp can be explianed by hypothyroidism.
Hashimotos thyroiditis ia an autoimmune disorder and antithyroid antibodies(like anti thyroid peroxidase
,antithyroglobulin antibodies) are required for the daignosis.
The Dental malocclusion
is not related to the Hashimotos thyroiditis and consult Dental sugeon for this problem.
Hypothyroidism requires thyroxine replacement so consult your Pediatrician
for starting thyroxine for your child.