1998 Dodge Avenger CV Joints

Transmission problem
1998 Dodge Avenger V6 Two Wheel Drive Automatic 160, 00 miles

I am getting two different stories and simply would like the truth on a subject. Are the CV joints (axle assembly) the same spline size, with the only difference being the lack of the excitor ring for the abs brakes and the model without abs?

I had purchased a CV joint, with the intent of my husband installing, he got busy so I took the car to a local shop (needed a new boot, but for the price difference we went with the whole assembly, I needed a new wheel bearing also, so no additional labor would be involved). I hired the mechanic to replace the bearing and cv assembly. He couldn't get the ABS light to go out, but had troubles with his computer clearing the codes. I took the car with the ABS light on, drove 10 miles and the transmission went out. All of the fluid had leaked out. Mechanic told me the shaft was the wrong size, didn't fit the hole, my problem. I went to the parts dealer, they told me the shafts are the same size, one is simply missing the excitor ring for the abs sensor and would not cause all of the transmission fluid to leak out, that the installer had probably shoved the seal sideways when installing? At this point the new boot looks like it is going to cost me $3000. And I am not too happy. My question, are the shaft ends the same size that go into the transmission on the abs and the non-abs assembly? Did the installer indeed shove the seal sideways?