If the passport is badly damaged, he needs to renew it in embassy. Otherwise, i mean, the info on the visa page is clear without any missing, it is Ok.

I see. If the passport was still looking good and just a little damage on the surface and the inner entrances stamp records was lose during washing, should him bring to renew? and how much for all the charges?

Thank you for the information.

yes, he should renew his passport because the the inner entrance stamp record was lost during washing. the fee is 440 Ringgits for renewing damaged passport. It takes 15- 30 working days, for more information, your Chinese colleague can read it on this website http://my.china-embassy.org/chn/lsfw/consularservice/chinesepassport/t174871.htm (in Chinese version)