My friend eventually being able to contact her friend who is working as prosecutor for labour department, representing the labours in those 被拖糧 cases.
My friend has briefly described your case to this prosecutor. The prosecutor doubted the "reply 莎朗 claimed she got from labour department. ".
anyway, the prosecutor will be back to Hong Kong tomorrow late afternoon and shall meet my friend for dinner and then they will call me.
If you can't settle the case by 20:00 tomorrow, pls let me know. I shall try to ask the prosecutor from the legal point of view about your case. I am wondering, apart from 未發放的工資, and 買送錢, your mum should also be able to get: 利息, 代通知金, 遣散費 ,