I have also read in Why not just use a small but unusual number of hashing rounds? that when there are multiple password to protect, the moment one is cracked the hacker will know for all passwords which is the number of iterations required. But if I have to protect just one file with one password (or a very limited number of files with the same password), does it make sense if instead of selecting 100000 iterations to protect the password I use a "random" number like 97334? Or is there an easy way for the attacker to know how many iterations they need to run?
The tool used in OpenSSL, and the attacker will have the encrypted file(s). The number of iterations to encrypt the key is not visible to the attacker.