listsinceblock incorrectly showing some conflicted transactions

[RHavar]

Normally when a transaction is conflicted, listsinceblock will show it as having negative confirmations, representing how long ago it conflicted. However, looking at the results of my listsinceblock shows dozens of conflicted transactions with 0 confirmations (as well as transactions whos parents have long been forgotten by the network).

An example:

{
  "account": "",
  "address": "1AM7qmzyzkZecxn5hTPUCbBbog3r3YbVyE",
  "category": "receive",
  "amount": 0.00684870,
  "label": "",
  "vout": 0,
  "confirmations": 0,
  "trusted": false,
  "txid": "f108f58235e35f3eb07d24d9d330f6098234137dd505bbd19ff249d809254f2d",
  "walletconflicts": [
  ],
  "time": 1493696422,
  "timereceived": 1493696422,
  "bip125-replaceable": "unknown"
}

Which would make you think it's a pending receive, so lets dive deeper:

bitcoin-cli gettransaction f108f58235e35f3eb07d24d9d330f6098234137dd505bbd19ff249d809254f2d
{
  ....
  "hex": "0100000001975c0acaefcc4abc471c5d9fe8de6ee5d6e76e7f01a089466f0a73c5f23dc36c000000006b48304502210088baffcff66ade8770a802888c868071291be4f6c6b7427e9938dbf2c9df6ee6022028a9a1af3e7e0ef4cdf42b3b6cc3113787e4db29922c1b90e182b2f1665be83e012102efdaa4cbd4fb4edd41978403a4343786462fefa514f98cbe1894f7053a1216c2ffffffff0146730a00000000001976a9146687296e39b87666fcbff34738c984eca686451e88ac00000000"
}

Decoding that, you'll see it's sourcing:
{ "txid": "6cc33df2c5730a6f4689a0017f6ee7d6e56edee89f5d1c47bc4accefca0a5c97", "vout": 0 }

Which is a transaction that has not confirmed, nor in my nodes mempool. Fortunately we can find it on tradeblock, and see it's conflicted with dd0ab2618d4df044d369b56ce96f6f8d9dca6e04f4c180fa73e8ace20b3653e3 which has long confirmed.

So this means that our original transaction is just sitting in listsinceblock is actually conflicted and impossible to ever confirm, yet not marked as such.