Currently, in the sharding_multiversion suite, we are seeding the random number generator for each replica set rather than seeding it only once. This makes reproducing the tests in sharding_multiversion more difficult.
This line here should instead be something like:

self.seedRandomNumberGenerator = opts.hasOwnProperty('seedRandomNumberGenerator') ? opts.seedRandomNumberGenerator : true;

Additionally, the check in shardingtest.js here should be checking jsTest.options().useRandomBinVersionsWithinReplicaSet instead of the no longer used jsTest.options().randomBinVersions.