The video shows various parts with varying sizes with an assembly linear velocity of (1000,0,0).
Yes this happens on the server too. Although I cannot follow the parts, using the print command (and using run instead of test), I can notice the discrepancy
Print data : Only the x coordinate matters
Camera subject Part1 (size 4,2,1) : 2788.673095703125, 117.50001525878906, 46
Part2 (size 4,1,2) : 2788.673095703125, 117.50001525878906, 20
Part3 (size 5) : 2834.507080078125, 117.50001525878906, -3
Part4 (size 10) : 2926.175537109375, 117.50001525878906, -25
Part5 (size 15) : 2926.175537109375, 117.50001525878906, -49
Part6 (size 20) : 2926.175537109375, 117.50001525878906, -81
Part7 (size 40) : 2797.001708984375, 117.50001525878906, -123
The only code is 1 local script with 1 line
workspace.CurrentCamera.CameraSubject = workspace.Part