Maybe something like this will work?
https://www.lowes.com/pd/VEVOR-50-in-Table-Utility-Cart/5015325273
It looks more promising than an adjustable desktop.
Rent? Buy, assemble, use once, return?
It is shown all the way up, OP would need something stable on top of it, to have it reach the bottom of the TV which is higher than that, and then get high enough for access to the outlet behind the TV, thus two steady stacks of ____? with space to reach in and position the power adapter, tie off the cord slack, ....
Maybe place some bookends on whatever ends up being the top surface, so when the TV’s weight is on them, they keep the bottom of the TV from moving forward away from the wall.
don't forget the essentials
wd40 and duct tape!

