Possibly the agent was only trying to be helpful in anticipating that an immigration officer could see an opportunity to ask for a tip/bribe? Alternatively, the agent could be touting for business if obtaining replacement/renewed passports are part of their service?
Immigration Officer's seem to be 'tightening up' in general, requesting photocopies of forms and documents they hadn't previously asked for. What they are asking from you sounds normal.
Depends how much you want/need to remain in Thailand. If you were to consult a Visa Agent they may be able to give you a price to clear your overstay, thus avoiding a ban.
Tumour is the symptom, the disease is the cancer cells in the bloodstream. Treating the symptom doesn’t cure the disease. Cancer doctors tell you very little because nobody wants to hear they’ve got cancer. My Mother recently died of metastatic disease. In the hospital MEU (Medical Evaluation Unit) they performed three tests; endoscopy, CT scan and, of course, the most reliable indicator, blood tests. All three produced false negative results until three weeks before death when the blood test results became abnormal. Later, I asked my GP if this was normal? She replied; “yes, it often is”. My GP took early retirement the other week as she now has breast cancer.