Will the visa office call to verify the unit phone number written on the Japanese group tourist visa and employment certificate?

You didn't say anything about traveling to Japan? Then why didn't you say you were going to travel to Japan, let alone call? You are easily rejected, because your purpose is not clear, so I suggest the landlord not to do so. There is also a phone number. If your assets are not convincing in this respect, I will definitely call you. Of course, it is impossible for a company to write a mobile phone unless it is a reference.