I would never try to book an award ticket with Thai by e mail.
Call the Thai Office and the staff in my experience are genuinely helpful in my experience, at least calling BKK. Of course others will disagree and have had a different experience and perhaps I am biased having lived in Thailand 20 years.
I would suggest that someone flying BC and FC would not normally have the patience to wait over 2 months for Thai to book an award and would find a way to expedite the matter; otherwise the deal is gone and several others wanting the award would have booked it by that time.