Cyclops makes a "smart" fluid 2. We've got 2x Cycle-ops fluid 2s in our house, one a decade old, the other newer. Both fit every bike in the house, mostly recumbents, but also several uprights. I've had them on: Volae Team, NoCom, Catrike Expedition, Rans Rocket, Bacchetta Giro 26 + uprights. The cycle-ops used to sell an adapter (just an extension) so that it could be used with a 20" drive wheel as well. We have also used them on several other standard fluid trainers that have passed through the house over the years, and they have all worked perfectly fine.
I like the fluid trainers because they've got a nice power curve that just requires upshifting and going faster to increase resistance, and they're fairly quiet and troublefree. They've got no tech on them, and they're reasonably priced. You can usually find one (or similar) on Craig's for less than $100, and there's not a ton that goes wrong with them.
On our floors they sometimes rock and make a creaking sound (but they'd do that on an upright, too). Grab a rubber weight-lifting or treadmill matt for underneath and you'll probably be happier.
The direct-connect ones even look like they'd work with the chain and chainstay lines of the M5 CHR, Kikr included, but if they're giving a blanket "no recumbents" recommendation in order to CTA, I wouldn't bother handing them the $1100.