From the Texas State Board. what are my chances of me getting this letter?
You should contact an attorney to see if it is possible to get the offense expunged. Depending on how your case was handled, this may be possible. State agencies can view court records even when there is an order of non-disclosure. You should seek legal guidance on getting the declaratory letter.
Nothing in this answer constitutes an agreement to represent you in any criminal case. Additionally, the information provided above does not constitute legal advice.