Guys...sometimes it's just not possible or practical to run cables for a camera (at least for a home environment). My previous residence required me to run two cams using wifi.
Can wifi be jammed/DOS'd? Sure. But my thought is that if someone is going to that much trouble, there's not a lot you can do except to hope that your other wired cams catch them somewhere else.
Regarding the OPs question though: The only Dahua cam that I see that supports 5GHz is the IPC-K35S 3MP cube cam. If needed for outdoors though, needs to be in a covered area. Not really outdoor rated.
IPC-K35S,IPC K35S,IPCK35S,IPC-K35
Otherwise, as Fenderman mentioned: Find a nice small client bridge device. Search for something like 'travel router'. Those devices are really compact and usually allow for a wired Ethernet connection. Those bridges aren't going to be outdoor rather either though.