It would also be helpful if you decode your transaction hex into JSON and post it here, erasing parts like addresses which you don't want to show if any. I suspect you could be having the same symptoms as the other thread, the vins having an empty ScriptSig.
More than that: you can run your client with regtest mode and then reproduce it with worthless regtest coins and paste results here. You can use one client as a miner, create some blocks and then use another instance of a regtest client pointed to different directory and different port, then try to sign a transaction from the second client. If both clients are disconnected from each other, it should be enough to reproduce it.