Hi,
If the SA1 was submitted on 6 September the UTR should have been allocated. You will need to contact our Self Assessment team to pursue:
Self Assessment: general enquiries
If your wife submitted a CWF1 then she would have a UTR but if she is not self employed she would need to contact HMRC to close the self employment record.
Contact HMRC
If your father receives foreign income then yes, he would need to register for Self Assessment.
Thank you.