Hi, I will try and assist with your query.
This is a very complex matter, and this forum is not appropriate to discuss your case. However, I will try and assist as much as I can.
If you have not done, you need to make detailed representations to the Home Office as to what his problems are in Saudi ( for example you have stated that he has overstayed his visa in the UK, his family are against the relationship and that you have not formally divorced yet). You could also add a witness statement from you as to why he should be allowed to remain in the UK or be released from detention.
I cannot comment why the Judicial Review application was refused because the Judge will look at what representations were sent to the Home Office (if any) and the judge will then consider the lawfulness of that decision under the public law. This is is very complex.
You state that your partner has applied for temporary admission, and it has been more than three weeks for a decision. Have you consider applying for bail to the Immigration and Asylum Chamber? This website may assist you: http://www.biduk.org/
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