Missing files/film footage from external hard drive HELP!

Hi,

I am a university student and have many film projects for my dissertation... as usual, I copied and pasted my raw files from a camera sd card onto my external hard drive put it in my usual dissertation folder and after some time it finished copying. It did 100% finish copying as i even played some stuff back from that folder to watch some footage. I safely removed my hard drive and sd card from the laptop and put it away. That same day i returned the camera to the university because it all copied onto my hard drive that morning so the camera then got passed on to another student, formatted and used to record more footage.

The next day, I plugged in my hard drive to the university computer and my folder I created in my dissertation folder which contained all my footage had disappeared and wasn't accidentally moved anywhere else on the hard drive. The original laptop which I used to copy the files show the folder I created and under properties states that the location is on my external hard drive, under the folder i copied it on to... but it definitely isn't there or 'hidden'.

I have no idea how this happened but my main concern is whether or not this data can be restored some how? My University ran a few scans of some software they have purchased in the past e.g. Ease US - but it didn't restore anything.

I've seen no data no fee advertised and was wondering if you think there is anything you can do for me?
Obviously, no data no fee would be ideal for myself as being a student I don't want to pay a lot of money upfront to not get anything out of it, but deadlines are approaching now and I can't help but panic.

I read something about command r etc but says I don't have permission even though i'm admin and I really don't wanna make any problems worse!