Inside of PS, you did a /file/save and not a /file/safe-as, correct?
Check your Library grid view. Sometimes the sorting of the new image from PS ends up at the end of the files instead of being placed correctly in the sorting.
I did both save and save as. I did check the library grid view. I am aware that the PS (tiff) files sometimes end up at the end; however, that is not the case in this instance. The only way I rectified the problem was to "save as" to my desktop and then import into LR.