Sh1t. Sh1t sh1t sh1t. I am so sorry. But I get the impression that the Mad Manager has decided that she doesn't like your DH and wants rid. So if it wasn't this, it would be something else a month later. I'm afraid that in male-dominated industries you have to be pretty forceful to get anywhere at all as a woman and though some are fabulous you do get some real rottweilers in there just by natural selection.
To be moe practical: (I'm using the word "you" here to mean "you and DH" iyswim.)
I think the first thing I would do if I were you would be to write a letter detailing the conversation with the manager. Leave out any abusive language, you'll never prove it - but stick to the facts. Just say that if you are suspended you would like written confirmation with reasons for suspension, and can she confirm that it is as per this conversation as discussed on . I would do this rather than asking her for her account, as by the time she's calmed down she may realise she's on shaky ground and start fabricating. So get your letter in (recorded delivery) first.
I don't think I would send it to her right away though. I'd then phone HR, and ask to speak to someone about their disciplinary process. Take the letter with you. I think the approach to take is that you don't understand the process they've applied to you as it doesn't seem to comply with EU employment regulations (this phrase should frighten HR) and you can't ask this manager as relations seem to have deteriorated beyond that point (show letter). 2 aims here: 1) to clarify to HR that a breach of law has taken place and that you do have some understanding of your rights and 2) so that when the manager (on receiving your letter) phones up HR with some wild fabrication of why you are suspended, they are already primed. It is key at this point to take an impossibly perky, eager-to-please approach: love the company, happy working there, good relationship with line manager who says am an asset, believe self hard working etc. etc; coming to HR more-in-sorrow-than-in-anger, etc etc. At all costs, you need to avoid being written off as a troublemaker when you walk through the door.
If, at that point, HR show any concern at all, I'd ask about greivance procedures against this manager. But an internal greivance procedure has no standing in law and so is only as good as the HR department that institutes it. If HR are not keen to enforce good management, it will get you nowhere.
CAB should get you contact of a legal aid lawyer who will give you free advice on where to go next. I imagine the lawyer will take the view that there is no point trying to repair the work situation; at this stage it is best to sue. But these guys only see the cases where direct negotiation and then mediation don't work out so maybe they will be right, and maybe not.
The other thing to ask CAB is what you will do for money while DH is suspended. I know a lot of people suspend on full pay but I don't know whether that is because you have to do it legally or what. But it's possible that they can be compelled to pay you, or that you can claim on insurance or something.