Might I make a suggestion?He can appoint his Chinese wife as his agent.They should visit the PSB in his wife's hometown.There she can discuss calmly how he can stay legally in China.
As for his renewing his Z visa,that may be impossible due to age restrictions.But I cannot see why he can't get an L visa for visiting a relative,namely his wife.He can go on renewing it thereafter,but of course he cannot work legally with it.And if he ever got divorced,he wouldn't be able to present his marriage certificate,and would therefore lose the right to stay in China on long L's.He should apply for a 360-day L visa.He'll get at least a 90-day L,which can be renewed before it expires.No need to worry.After 2 years of L visas without leaving the country,he will automatically qualify for 360-day residence permits,which will save the pages in his passport.But should he leave the country at a later date,his residence permit will be taken from him at the exit point.Then he'll revert back to L visas on his return,the initial one applied for outside China being only a 30-day L visa,which can be renewed within China as and when necessary on presentation of his marriage certificate,wife's hukou and apartment rental contract.