1992 Plymouth Voyager transmission or CV joint

Transmission problem
1992 Plymouth Voyager 6 cyl Front Wheel Drive Automatic

92 ply voyger 114k miles
When turning corners heard clicking noises around turns so had the cv joints looked at. Got a good quote from les schwab and had the repairs ready in a week well my van did not hold up for it. Making a U turn and very loud clicking and just started grinding and had it towed home and waited for the repair day and had it towed to les schwab and they kep it for about a half of a day and called me back to say it was not the cv joints its the transmission gears but there not sure now where did I go wrong here
also to note the vehicle was not able to move in park after the repairs were suppose to be done it now rolls in park I believe they tryed to drive it after I told them the cv joint are shot .