There was no indication of taking a T4 med, so that is a good question. Beyond that, mkh9, I disagree with your post saying TSH should be the main lab result. TSH is a pituitary hormone that supposedly is an accurate indicator of thyroid status; however, extensive scientific evidence has shown that this is not the case. Due to the many variables involved, TSH has only a weak correlation with the actual thyroid hormones, and a negligible correlation with hypothyroid symptoms, which are the source of patient complaints.
The only time TSH is an adequate diagnostic is when it is at extreme levels. Because of the poor correlation of TSH with the actual thyroid hormones, TSH should not be used to determine med dosage. Symptoms correlate best with FT4 and FT3 levels taken together, not with TSH. Dosage should be adjusted as needed to relieve hypothyroid symptoms. You can confirm what I have said by reading the latest paper I co-authored, shown in this link.
https://thyroiduk.org/wp-content/uploads/2022/10/Patients-Guide-Final-V5.pdf
TSH is a pituitary hormone that stimulates the thyroid gland to produce natural thyroid hormone. When the TSH is high, it is a signal that more thyroid hormone production is needed. When TSH is basically zero, that indicates there is more than enough serum thyroid hormone.
So your wife's test results are indicating that something other than TSH stimulation is resulting in her thyroid hormone levels. For that reason I suggest that she should see an Endocrinologist, to get an ultrasound test of her thyroid gland, to determine its condition. Dependent on the results, it might be necessary to test for the possibility of Graves' disease, by testing for TSI (thyroid stimulating immunoglobulin).
Please let us know results.
Test results and associated reference ranges vary from lab to lab, so to assess your results, we need you to please post the reference ranges shown on the lab report for those results. Even more important than test results, please tell us about any symptoms you have.