[SpinnerCee]

Grossly unequal L/R tire pressures on an axle could cause enough of a wheel speed difference to cause a false ABS/Traction Control indication.

Different brand tires [of the same size] on the same axle could do the same.

Keep in mind, the above are not likely to get your repair shop any cash, so don't overlook them yourself, or expect them to suggest the obvious.

It's strange that the indication only occurs at speed if a wheel sensor was improperly connected due to the axle replacement, but it does happen. Think also about what else was changed. ABS wheel sensors constantly monitor wheel speed, so strange issues like yours usually involve things that may differ betwen wheels.