We Live In Charlotte NC, So The Weather Is Still

We live in Charlotte NC, so the weather is still hot..90's. My husband had AFIB and cardioversion 3 yrs ago. He has been good since then and takes amlodipine 2.5 mg and 81 mg aspirin daily. He is 30 # overweight, his BP is controlled, his A1C is elevated . Monday night he was sitting outside smoking a cigar and having a glass of bourbon with a neighbor. When he stood up to sit in the shade he suddenly began sweating profusely and got dizzy and a little disoriented, felt like he could lose his balance.
Wouldn't go to the hospital. Went to ER next morning. CT, blood work, chest xray, neuro check all fine. Was advised to be admitted for stress test, MRI of the brain, carotid artery and chest echo., he refused.
He resumed work.
This afternoon he called me at work and said he wasn't feeling well. He admitted he has been experiencing the same pressure in his head and face (not a headache), equilibrium is off and when he walked down a hill to take out the trash felt like he was going to lose his balance.
He doesn't want to go to the ER which I KNOW we should and wants to wait to see if the symptoms clear up.
The ER doc said when his patients sweat, he sweats. He said the MRI would show if he had, or is continuing to have TIAs.
I explained to him he could be having multiple TIAs and that's why he's having the continued dizziness.
What other causes are there? I'm desperate for him to go to the hospital but won't. He thinks everyone is going to tell him to go and unless he sweats again or feels worse he is gong to wait it out.
Need help!