[Samsung Galaxy S21 Ultra] samsungs21:
Problem:

My mum has an Android-based Samsung phone and unfortunately, when the main folder with photos ("Camera") was moved from the Phone to PC via USB cable, it was made using Cut and Paste. By accident the files were pasted into Recycle Bin and we received warning "Files will be permanently deleted. Do you wish to proceed?". We pressed "No" to abandon this process and undo the mistake. Nevertheless, the entire folder "Camera" has already disappeared from the window of DCIM folder on the phone (as viewed from PC). Similarly, the folder appears to have been deleted when viewed from within the phone. (also the phone now has 150 Gb free, while before the process it had 110 Gb free, so it appears 40 Gb of photos have been deleted....

Attempts to fix:

Standard photo / data recovery services failed to bring results (searching hidden folders using Windows Explorer, Total Commander and Ultdata Android).

We then tried two professional software solutions (Cellebrite UFED and Oxygen Forensic Device Extractor -- Android Agent), which also did not manage to locate photos on the device.

It appears as if they were completely deleted.

The same person who used the two prof software solutions above has access to PC-3000, but he claims it's not suitable for Android data recovery (?)

We have already spent 2 days and hundreds of dollars on consultations, which unfortunately still have not brought any results, while the emotional weight of deleted memories is haunting us. Thus, we appeal to help of this forum.

Current thoughts:

#1 All other methods suggested require rooting the phone, which apparently will wipe the whole and make recovery of that specific folder even less likely (correct me if I'm wrong).

#2 All suggestions to make back-up of the phone / clone the entire memory are not relevant, as the only files that are of importance here are the files in the deleted folder, and those files are not hidden and therefore will not copy into this back-up anyway (correct me if I'm wrong).

#3 One person told us to ask Samsung customer service, but their response was that they don't do data recovery and that they only can restore if there was Samsung cloud backup activated.

Questions:

Q1: What is our best course of action? It seems, rooting is one way or another, inevitable. What rooting method would be best to use here, given the situation and my phone specifications? I understand that there is no 100% guarantee to recover the erased photos, but we would like to at least give it a try with maximum chances of success.

Q2: Given that the files we want to back-up are already deleted and not visible, is it even worth it to try to make any back-ups? or will it be in vain, and should we just proceed to rooting and further recovery attempts?

Q3: IF, we successfully root, what is the best way to access the hidden data? Do we need help of this expert who has PC-3000 and specialized software, or is it going to be accessible using our own PC+USB cable + extra downloaded software?

Phone:

Samsung S21 Ultra (G998B). Android 12. No cloud, no backup. Phone not used for now. New data is not copied onto the phone. Phone not rooted.

Thank you for all your help. I do hope to find some solution. We are down hundreds of dollars, many hours of talking to consultants, many of whom appear to just google potential solutions and offer us some basic things, while the pain of cherished memories potentially lost forever is the worst, much worse than money lost. Any help or constructive feedback would be appreciated!