Refer to the Commentary to section 230.8(a)#3 & #4 for more info on what is considered a fee:
3. Fees affecting “free” accounts. For purposes of determining whether an account can be advertised as “free” or “no cost,” maintenance and activity fees include:
i. Any fee imposed when a minimum balance requirement is not met, or when consumers exceed a specified number of transactions
ii. Transaction and service fees that consumers reasonably expect to be imposed on a regular basis
iii. A flat fee, such as a monthly service fee
iv. Fees imposed to deposit, withdraw, or transfer funds, including per-check or per-transaction charges (for example, $.25 for each withdrawal, whether by check or in person)
4. Other fees. Examples of fees that are not maintenance or activity fees include:
i. Fees not required to be disclosed under Sec. 230.4(b)(4)
ii. Check printing fees
iii. Balance inquiry fees
iv. Stop-payment fees and fees associated with checks returned unpaid
v. Fees assessed against a dormant account
vi. Fees for ATM or electronic transfer services (such as preauthorized transfers or home banking services) not required to obtain an account
Sounds like a dormant fee which is listed in 4(v). If this is true, I believe you can charge this fee and still call in "free."