The answer is no. I could hack it in with the UE source build but I promised myself I wouldn't resort to that except in dire circumstances.

Basically, proper support for detecting controller types is just not something UE4 does. Apparently a lot of people are OK with this https://twitter.com/stevestreeting/status/1247930318381776897

I'm not sure why this is a hill I'm willing to, if not die on, at least be critically wounded on (res me dude). It just seems like something I should do.

Also, choosing which of multiple controllers attached to the PC to assign to a player is just not a thing in UE4 either.

There's no option to assign all controllers to 1 player (so I have to reboot my PC if my 360 controller gets stuck on P2 and I want to use it, wheras with Rewired I could just use any if I wanted). And there's no runtime interface to allocate controllers to players.

At first glance UE4's support for gamepads on PC looks good, but as soon as you start dealing with anything other than 1 Xbox controller it just kind of throws its hands up and gives up. I know I've been completely spoiled by Rewired but still, disappointing.

I’m off to beg @GuavamanEnt to make Rewired for Unreal now