I need some help/advice with booking overnight trains.

I need some help/advice with booking overnight trains. We definitely want to do it.I have been trying to follow booking advice recommended by seat61 and some others.I need to book cabins for 5 adults. We want the whole cabin so it’s either 1 x 2 cabin and 1 x 4 cabin, or 2 x 4 cabins. The latter option seems to work out cheaper and most available to be honest.I am repeating our names to secure the additional beds in the cabin. I tried lotus and their website was straight forward, but now sold out. So back on 12go and balou.So my questions: If I add 8 passengers and select the 4 bed cabin, will I be provided with 2 cabins as needed? Sounds daft but isn’t as clearly stated as it was on lotus who clearly listed 2 cabins in the basket for payment. The se19 train isn’t available so are se1,2,3,4 ok?Are there any other sites less complex / easier to use where you can clearly select 2 cabins and know what you are purchasing? Any help and advice is really welcome at this point.