This kind of thing is not unique to the Kadjar and faults can clear themselves and the repair garage won't necessarily find any fault codes.
As an example, I was driving my works vehicle, different make and vehicle type, and was accelerating hard away from a roundabout on a dual carriageway when suddenly the power backed off to the point I was struggling to get above 2000 RPM and all sorts of warning lights came on along with messages like Check ESC, Check Hill Start Assistance, Check Injection System.
I pulled over in the next layby and waited for the RAC. They plugged in the computer, yes there were multiple fault codes. Started the engine and it was like nothing had happened. Drove back to my home town, with the RAC following, and it was like nothing had ever been wrong except for the warning messages. So this happened on a Thursday went straight to the dealer, they could not do anything there and then and it was suggested even if they plugged in the computer the codes are likely to have gone but booked the vehicle in for the Tuesday. They suggested I leave the vehicle with them which I refused as the vehicle appeared to be drivable and there were no RED warning lights only Amber, along with the warning messages.
The warning messages and lights started to disappear before Tuesday and all is well and I cancelled the dealer visit. This all happened back in January and, touch wood, no further issues.
I recently got the Gizmo to plug into the vehicle to check for codes and there is nothing showing.
Sometimes it can be as simple as a sensor glitch and nothing serious and other times not so much so.
Always respect the lights and make a judgement call.