Good news: You can get a digital version – legally. Here are the best options:
Buy a used physical copy from eBay or Booklooker. However, be cautious: the access code for audio downloads may have already been used. Look for sellers who guarantee "unused code." Menschen B1.2 Arbeitsbuch Pdf
If you study 1–2 hours per day, the workbook will take about 4–6 weeks to complete thoroughly. Good news: You can get a digital version – legally