[Solved] Just signed in to Opera Sync on my Desktop, which is my primary computer, after signing in to Opera Sync on my laptop which is basically a fresh install of Opera. Once the synchronization was completed, all of my Speed Dials on my Desktop were suddenly deleted. I could not tell if the same deletion occurred on the Laptop, as there were no Speed Dials loaded as yet on that machine.
On my Desktop, after failing to find a solution online with a cursory Google search or in these Forums, it was easy enough to resolve, at least in my particular case, by simply opening the Bookmarks inside a new tab in Opera, then selecting the entirety of what appeared to be a new Speed Dials subfolder (which for me was located near the bottom of the Bookmark tree structure, then performing a right-click to open the context menu and selecting "Copy", then finally clicking on the main/parent Speed Dial folder (located at the top of the Bookmark tree structure-which was empty- under the Bookmarks Bar folder) and performing another right-click for the context menu and selecting "Paste".
All Speed Dials returned to my Speed Dial page on my Desktop. Went to laptop, closed and restarted Opera, and waited nearly an hour (just in case) before reloading Opera. No Speed Dials are there, even after assuring the Synchronization was signed in on the same account. I'll just copy and paste the same way after exporting my bookmarks from my Desktop and Importing them into my laptop.
Problem solved.