Broda Barnes popularized using basal body temps as an indicator for hypothyroidism. Its a good barometer but not something you should use solely to assess thyroid function.
Focal or systemic immune system activation can cause a factitious temperature elevation. If there is subclinical sinusitis, for instance, the oral temp may seem normal or slightly elevated in a person who is hypothyroid by all other clinical measures. If there are pockets of inflammation systemically,temps in other areas will be elevated. Normally, if there is low thyroid function, feet will be cold-usually in the 70's. This person has a temp in the 90's which would suggest there is no thyroid problem. The rest of his exam reflects otherwise.