OP - I echo all the PP’s on here applauding your strength and courage in getting to this point.
I hope you’re able to contact the specialist organisation mentioned above in order to talk - they aren’t “the authorities”, they have been set up to help people who have previously been let down by those in authority.
I hear how tough the place is that you’re in right now but, if you can, take a moment and consider what steps you would need to take to be safe from your husband and protect your children. Starting again somewhere new won’t do that. You think your H won’t see the children because he will want to see you struggle - that may be true. But from what you said about his manipulation of them today (?) or very recently, it sounds to me as though he is more likely to ensure he does see them because THAT will also be difficult for you. He will put his need to control first and everyone else’s second.
Youre in a strong financial position - have you taken any legal advice on what would happen if you divorced/if you refused to sign his visa and divorced/if you refuse to sign the visa and report him and divorce? My guess is that the support organisations mentioned might be able to recommend a lawyer who would be able to talk you through that.
You have worked so hard, studied and qualified as a teacher and so on - you must on some level know that information is power. Get as much information as you can, for free and paid for, then try and figure out what is right for you and your children. Being a single parent is hard, but parenting while someone else actively tries to drag you down is infinitely harder. If you’ve got this far then solo parenting is very unlikely to be the straw that breaks the camel’s back.
If you have never come across it then I recommend downloading (discreetly) Why Does He Do That? By Lundy Bancroft - not because it’s necessarily going to tell you anything you don’t already know about your husband, but because it is truly compassionate and insightful about the effects of abusive relationships and might help make you feel ‘seen’ and validate some of the ways you’re feeling.
You may need to have separate talks with your children about what their dad said - 10 and 5 are very different ages. But it’s ok to say there are problems and that you’re working through to determine what’s best. All you can do is let your children know you love them. (And no five year old could reasonably be expected to cope with that kind of emotional pummeling - no wonder they went to bits. It doesn’t mean they couldn’t manage without him - and in the future they might come to understand better what’s gone on).
You've created a life which, externally, probably looks like the life you’d want. Your children won’t be bamboozled by outward appearances forever. Reach out for help where you can and try and make the emotional reality of your life something you can admire as much as you feel pride in your many accomplishments and strengths.
hang in there, one step at a time 💐💐💐💐