Before giving me credit where it isn't due... I only found a vendor website selling the ESC and then provided a link to the PDF they had linked to... So I only found an existing document. So it isn't "my" PDF, just a link I provided.
Your translation about the LVC is correct and is in fact listed in the Features area on the PDF right after the number 1 item listing.
I would also doubt that the ESC is losing it's setting even if it is a slim possibility, in fact it's unlikely since the LVC default setting is Mid, that is what it would revert to had it lost them. On the other hand, the reason to check and verify the setting would be if the user had accidentally changed the setting thinking they were changing something else. Once that is verified to still be at a Mid setting, you have then eliminated one of the three possible known causes. I'll come back to a LVC issue in a bit but wanted to cover why I mentioned checking the setting first.
The "loss of throttle signal" ... I'd only see this as a possibility if the receiver lost a signal with the transmitter. That would also mean none of the other controls would work either. I've never heard of just a single channel being lost in a loss of signal situation, if you lose one, you lose them all. I would assume you would have noticed no controls working at all but I also could see being concerned enough over the loss of throttle that the loss of everything may get overlooked... again less likely and even almost doubtful but we are talking about possibilities here so it's covered just in a case. Oh... it may be worth your time to check that the servo connection at the receiver is good and hasn't worked loose. In fact, just unplug it and replug it a couple of times to make certain minor corrosion at that connection isn't an issue.
Double check the wires going from the ESC to the motor as well. Like the connection from the throttle on the receiver... if you use bullet connectors ( or whatever type ) plug and unplug them a few times to ensure they are tight and also haven't developed some minor corrosion. If there is a poor connection now, this could result in it pulling too many amps which would drop the voltages and result in a LVC situation.
Your hobby shop has already covered the motor as another possible cause of high amp draw that could result in a LVC happening. Dirt in the bearings and other areas, minor damage that bends something in the motor would be the more likely causes for a motor issue.
Bindings in the other areas of the drivetrain would also be a possible cause of a high amp draw resulting in a LVC situation. So check the main rotor and the tail rotor for this as well.
So cables and connections would be my primary suspects and drivetrain issues my second... the last would be the ESC LVC setting but as I mentioned, it's the least likely but at the same time probably the easiest to check.