I lost all my progress on pvz2

My guess is all player's game save progress are stored both on the server and possibly on a backup server for protection.  

When a player delete the game on the local gaming device, the game save progress of that account still remain on the server, EA has provided a self recovering service for the player, this is by registering an email address to tie to the account, this also enabling player to install the game on a different device and even with a different operating platform.  

Sometimes unexpected errors occur (either by man made or by the computer) and the recovering failed, the Help Center staff can assist to recover the data manually but this is a time consuming process.  For this to be possible, one critical information is the player ID for that account, without this, it would like looking for a needle in haystack, I think there might be other unique details from an individual account can be given to narrow down the search, so yes, it still can be done without the player ID but I am not sure how you can persuade an advisor to spend a few days or even weeks to go through all the inactive accounts to pick out the one which is belonging to you.