It would be best to show some screen captures. You state you select two frames and use tween to generate frames between these frames. The frames generated are not what you expected. The thing is we have absolutely no way to know anything about the two Frame you selected. Their layers composition the Document layers used or their positioning or their masking their opacity in the two frames.
Here I create two frames using two layer where one layer has a layer masked the is not linked the the layer's content and is a mask to composite the layer with the contents of the lower layer. The top layer content was placed high and off canvas to the left and the second frame that the layer content was positioned low and off canvas to the right. I user tween to generate 148 frames between the two frames I created using the two layers. The opacity blending is was I expected the layer mask to produce.
I never tried layer transforming to resize or rotate layers. I just tried to do your turntable and it looks like tween layer position only supports layer position over the canvas. I was not able to get layer rotation via transform to work with tween. I had to resort to using a script to duplicate the layer and rotate it about a point by so many degrees, I could than use create frames from layer to create a frame animation the add a background visible in all frames.
In the past I did create video animations where I rotated a Photoshop 3d layer's object.
Yeah, that's what I ended up doing, as well. Created 25 duped layers, rotated each around the same point by .5 degrees, then created the animation from the layers. When I converted that to a Video timeline, the motion smoothed out more so there weren't the discrete steps visible. It's fine, just more work.
You may be right that the tween function works on movement, but not a transform operation. If I move the position of the arm with the Move Tool, the tween works, but not using Transform.
Thanks for the help.
If you could please delete that turntable graphic from your system, and wherever it's hosted, I'd appreciate it. Thanks.