Even taken at their word, it doesn't change the fact that they are using documentary procedures that are unusual, and abnormal. Contact any business college, or speak to established traders or people working for large multinational corporations. Talk directly to international bankers on this.
Some brokers advise to skip the LOI and go straight to the purchase agreement and an LOI is not typically used in the market at large. So, why do we advocate the use of an LOI when purchasing a business?