Odd that Smart Switch didn't successfully restore your phone call log into your new phone, especially since you can see that EXML file within your Smart Switch backup.
But moving on, do you still have possession of your old phone? The following depends on you being able to make a backup of just the phone log on your old phone to transfer into your new phone. Install the
SMS Backup & Restore app on both phones, make a backup for just the phone call log on your old phone and then use the app on your new phone to import it. Yeah, the app's name refers only to SMS text messaging but it does include a feature that involves phone call logs too.
Anyway, that Smart Switch file, the EXML file is the
Encrypted
XML file type that Samsung created for its backup utility. The encryption prevents you from being able to successfully view its content with something like a text editor by design. The text appearing to be just random characters is intentional, which is actually a nice privacy aspect as some of the data in your backups is secured. Using the SMS Backup & Restore app will allow you to make a plain (not encrypted) XML file. Note if you opt to view it first in a text editor will still consist of a lot of jumbled characters, a mix of recognizable phone numbers and names with necessary formatting commands.
A file with the .xml file extension is an Extensible Markup Language (XML) file. These are really just plain text files that use custom tags to describe the structure and other features of the document.
www.howtogeek.com
If however you don't have your old phone, just some random suggestions for your current, new phone (...that I'm assuming you've already tried?)
-- Be sure to just restart your phone just in case that imported EXML file needs to essentially get loaded into memory and/or the Phone app itself.
-- Try Force stopping the Phone app itself, and delete the app's cache and see if your call log is showing up properly.