I cannot count how many times I've had my elbow or foot banged on by the service trolley. In each case, the crew noticed immediately and apologized. Honestly though, its my fault - I should not be using the isle as my personal stretch area.
I am honestly surprised that they did not do the same on this occasion. In order for the cord to be bent at the jack, it would have had to been caught by the trolley, and with significant force at that in order to bend and damage the jack (vs. just having it pop out of the socket, as it happens many times, or simply have the wheel roll over the cable - also happened to me a few times).
Such a force should have been noticed by the flight crew - and frankly, by yourself. Its not an insignificant amount of force.
In order to get reimbursement (and I'm assuming from the airline), you'd have to claim some sort of negligence or fault on their part.
As you never notified the flight crew at the time of the incident (in order for there to be a record of it) - or during the remainder of the flight - the airline can claim that the item was damaged somewhere else and you are just trying to get the airline to pay for it; and you have no recourse here.
The only claims procedure I know of at airlines is for luggage and not personal electronic items. So I am not sure what/how you would even begin here.
I would recommend:
Checking with your travel insurance or item warranty to see if the item is covered.
Just buy a new cable.
Call the airline customer service desk call center and explain your situation; although again, I am not sure how much they can help since you never reported the incident to the flight crew.
In the future, if you run into a situation where your personal belongings have been damaged due to negligence of the flight crew - you should immediately notify them of the action; and notify the flight purser (the senior flight attendant). They will know the procedure and if there is any paperwork to be filed for claims/reimbursement.