mongodb balancer does not move chunks because of obscure error - mongodb

Question

After carefully following this guide, on how to migrate a 3 member replica set to a shard containing 2 X 3 member replica sets, after sharding one of my collections nothing happened. Looking into the logs, i got this:
2014-06-22T16:49:55.467+0000 [Balancer] distributed lock 'balancer/vt-mongo-6:27018:1403429707:1804289383' unlocked.
2014-06-22T16:50:01.830+0000 [Balancer] distributed lock 'balancer/vt-mongo-6:27018:1403429707:1804289383' acquired, ts : 53a70939025c137381ef2126
2014-06-22T16:50:01.945+0000 [Balancer] ns: database.emailevents going to move { _id: "database.emailevents-_id_MinKey", lastmod: Timestamp 1000|0, lastmodEpoch: ObjectId('53a6d810089f342ad32992d4'), ns: "database.emailevents", min: { _id: MinKey }, max: { _id: -9199836772564449863 }, shard: "replicaset2" } from: replicaset2 to: replicaset4 tag []
2014-06-22T16:50:01.945+0000 [Balancer] moving chunk ns: database.emailevents moving ( ns: database.emailevents, shard: replicaset2:replicaset2/vt-mongo-4:27017,vt-mongo-5:27017,vt-mongo-6:27017, lastmod: 1|0||000000000000000000000000, min: { _id: MinKey }, max: { _id: -9199836772564449863 }) replicaset2:database_replicaset2/vt-mongo-4:27017,vt-mongo-5:27017,vt-mongo-6:27017 -> replicaset4:replicaset4/vt-mongo-1:27017,vt-mongo-2:27017,vt-mongo-3:27017
2014-06-22T16:50:01.954+0000 [Balancer] moveChunk result: { errmsg: "exception: no primary shard configured for db: config", code: 8041, ok: 0.0 }
2014-06-22T16:50:01.955+0000 [Balancer] balancer move failed: { errmsg: "exception: no primary shard configured for db: config", code: 8041, ok: 0.0 } from: replicaset2 to: replicaset4 chunk: min: { _id: MinKey } max: { _id: -9199836772564449863 }
2014-06-22T16:50:02.166+0000 [Balancer] distributed lock 'balancer/vt-mongo-6:27018:1403429707:1804289383' unlocked.
generally, this error:
result: { errmsg: "exception: no primary shard configured for db: config", code: 8041, ok: 0.0 }
is the result of the machines not being able to talk to one-eachother, but this isn't the case. I have manually checked and all the machines are able to talk to eachother.