possibly but if he can show he appeared to extend stanp but full book may not depends on IO and the pull of his ambassador. Then again they advise and warn everyone to make sure your passport is at least 6 months valid and have pages left, so you maybe right.
The seasoned account is dependant on embassy you use honestly seen people get by with 1 month statement. If you are worried about visa exempt and want to season your account anyway, apply for a student visa to get in selecting thai boxing cooking or language as a suggestion, then after the year is over upgrade into DTV
Or you dont have to wait the full year and process upgrade in the middle but you will have to leave thailand for DTV anyway, why I suggest waiting for the year to end ( you would have to leave anyway )
Contact embassy to get new passport they should be able to assist him with this issue may still have a fine to pay but hopefully not a ban. A full pass port book is always an issue