A wrong rest file can brick your phone, but as long as you have a good GDFS backup, the phone can be revived. But it looks like the rest file you found is good. JDFlasher and SETool2 Lite use the same rest files, except they use different file naming convention. But if the phone works, then there is no problem :)

Why you search for rest files when you can make one with [FarManager_folder]\Plugins\jdflasher\rest\mkrest2.exe
Usage: mkrest2 Your_MAIN_firmware