Husband is in South African and I am in China with our 4 minor children.

My husband left on the 2nd March to be with his father that fell ill, and to help our son get his papers ready to join us in China. The borders closed in that time and he has been stuck and quarantining for more then 129 days.
I have an invitation letter from our agent and a letter stamped from the exit and entry bureau from Bazhong.
It is for reuniting of our family and to start working as soon as possible to help provide for our children. I have been working but had to send money home to SA to help with finances and have to look after our 4 minor children on my own. It has been very hard, since the children are yet to go to school and we need funds to do so. Can my husband get an visa on arrival at the airport and what is the procedures in doing so? He has a valid passport, residence permit and work visa, with his invitation letter.
The Visa office is still closed in South Africa, so he can not apply for a new visa to enter.
What advice do you have for us please?
Thanks in advance.