This thread is resolved. Here is a description of the problem and solution.
Problem: Strange strings with numerals showing after migration of site and activating WPML String Translation
Solution: There was a known compatibility issue between Duplicator and WordPress 4.8.3 - https://wordpress.org/support/topic/percent-sign-gets-hashed-due-to-update-in-esc_sql-in-wordpress-4-8-3/
Please try to migrate again creating a new package using an updated version of the Duplicator plugin.
If it was not the case and while another supporter takes personal charge of your situation please give us more info about the migration process.
Let us know if it helps.
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