Is family visa from Pakistan open?

Yes TE letter is still required as without TE letter no visa is being issued by the Chinese embassy in Islamabad (keep in mind Chinese embassy in Karachi and Lahore are still closed for visa issuance facility and applicants have to travel to Islamabad for visa). TE letter can be applied by the employer of your husband and its a little long process as takes about 4 to 6 weeks depending if all requested documents are submitted by the company in one shot and there are no further enquiries by the govt. dept.
The Govt dept. will ask for the tax paid by the company and personal tax paid by your husband, his salary and residence etc.