Why does alpha channel black out border of TIF image

Please read this (in particular the section titled "Supply pertinent information for more timely and effective answers”):
https://community.adobe.com/t5/using-the-community/community-how-to-guide-tips-amp-best-practices/td-p/11601738?page=1

Could you please post screenshots with the pertinent Panels (Toolbar, Layers, Channels, Options Bar, …) visible and illustrate your problem? 

Hi JJ (and anyone else reading)

Here's the project in PS. It's zoomed out and the thin black frame is due to me including black workspace in PS to show the boundaries of the project image.  Note there is also a title below the image.

Here's the PSD file saves as TIF and viewed on ImageKind.  The white "frame" their preview frame.  The entire border including titles has become black.

Fundamentally, the background layer is a photo of an old print including the faded paper around it.   Layers above that adjust the core image, the outer wide border (it's about RGB 205, 205, 205 in final) so it's not brilliant white, and other details. 

The project is saved as PSD but the final file for printing is indeed Saved As, in TIF.   I didn't use Export.

In this view and when printed from PS myself, it's as shown.  There's a white border around the core of the image.  Not actually white, that would be too bright, it's 205, 205, 205.

When I flatten the layers and save as TIF then upload to ImageKind, the border become black.  I thought it was a difference in their system so I deleted all layers and tried again and also viewed it in Windows Photo Viewer, and same problem in Photo Viewer, therefore it's something about the TIF file.  Everything outside to core image is blanked out if the alpha channel is included in the TIF file.

ImageKind preview:

Windows Photo Viewer:

If I omit the alpha channel when saving then the image does look correct.  Here's the preview from ImageKind:

Here's one idea. 

There are three adustment layers with masks around the core image: two brightness/contrast one masked for the border and one for the core image, and a gradient map layer also with a mask around the core image.  Remembering that the problem still exists in the saved TIF version even if I *delete* all layers except the background (original image) layer, could one of those adjustment layers with their masks, have created a masked alpha channel with the shape of that border that is now part of the overall PSD project file instead of being part of only the layer that created it, or needs it.

It would still be wrong though for that alpha channel to wipe out the border, and for this result to only be seen in the TIF, but not in PS and not in the print from PS.

Very odd.