That is, for a fact, a 185S/200S fork.
You're correct that is a E/ES. Doesn't matter though, the original E/ES fork top bridge won't work, it's narrower than the 185S/200S top bridge. Ask me how I know that.
There isn't anything going on here I haven't done or seen before. It's all pretty cut and dry and also why trying to piece together forks instead of buying complete ones has it's pitfalls. There's enough differences that one must know by only looking, because things like Ebay listings are from ATV dismantelers who are NOT trike enthusiasts and their listings are often incorrect. So many of these trikes have had
parts swapped that even reading the VIN is likely to be incorrect for the part.
If this is setting them back, wait until they find out that fork doesn't accept the E/ES front wheel and tire. The front hubs won't interchange and the bolt patterns are different. Even with modification, using a 25" tire, it will always rub the fender over little bumps. Best, quickest, lowest cost action would be to use smaller rear tires to level it out and just use the 22" front tire. The ideal fork for that swap is from a 200M, but those have the issue of no new front fenders being available, except maybe through Maier, which is $140. Good luck finding a nice used 200M fender, because even if found it'll cost more than that. Fork swaps can get expensive quick, if the whole thing isn't planned out thoroughly, every detail.
We still don't even know if they've already bought the headlight brackets and bucket for those forks, because the E/ES
parts won't work. Obviously, the front rack won't fit either, but that can just be left off. It's not much work to weld tabs on the fork for the rack, but not everyone has a welder.
Working with limited information.