Iphone no longer showing up in itunes after 17.3.1 update

Hello, I am in desperate need of some help here. After upgrading to IOS 17.3.1 on my iphone 13 pro it is no longer being recognized in Itunes. (I am using a macbook pro running El Capitan) I have tried just about everything known to man and it still wont work. I need an apple guru or someone that knows more than I do :| here are the trouble shooting steps I have tried and none have worked.

1) Tried various cords (and no usb hubs in between)

2) I called apple support and they recommended restoring the phone to default, which we did and that made it WORSE because now my phone is blank with no music/pictures/apps etc I lost everthing

3) my phone is backed up however it is backed up on the computer that stop reconizing the iphone in itunes

4) this seems to be an ITUNES ONLY problem, the phone shows up in the system details, it also shows up on photos, it also shows up when running the "image capture app" basically shows up EVERYWHERE except itunes.

5) I plugged the iphone into another mac and into a windows PC and it is found right away with no issues.

6) was going to downgrade phone to 17.2.X however apple won't sign those versions so that's not an option.

7) was going to try different versions of itunes but they are not supported and won't install because i am on El Capitan 10.11.6 (which is the lastest and last version of El Capitan)

8) upgrading my laptop to a newer version of the OS is not an option, I have thousands of dollers in music production software on this PC and all my plugins in Logic X that I use will all break and I would have to purchase them all over again...............

9) there is no firewall, no 3rd party security apps of any kind on this macbook pro.

10) I have another iphone 12 but it is also on 17.3.1 and it also wont show up

11) I have older iphones that are on 16.x.x and they do show up.

12) tried downgrading the iphone back to 17.2.x but apple wont sign that version anymore so downgrading the iphone is NOT an option (thanks apple for that)

13) I uninstalled itunes and reinstalled tried two different versions since those are the only ones that will work on El Capitan (made no difference same issue)

14) Tried recovery mode (volume up, volume down, hold power till apple logo) and no luck.

15) I even tried using time machine to revert back a couple days (when it did work) but that didn't help either problem still there.

TLDR:

Any phone that is on 17.3.1 will NOT work with my mac now all the sudden, issue just started once I went to 17.3.1, two different phones have the same issue, my older phones that are not on 17.3.1 DO work. apple support had me wipe the device thinking that would fix it however it did not. so now my phone is blank and the backup is on this laptop but I cannot restore it because itunes refuses to see it. Every app on my mac will see my iphone EXCEPT itunes. which is the most important part since that's how I sync and back it up.

So at this point I am in a very bad situation; with a blank phone, no pictures no music, no apps and no way to restore a back up even though there is one stored on my pc it requires itunes to load the backup.

I have tried everything possible as you can tell from allllllllll the steps above.

I'm super desperate at this point, if only apple would allow me to roll back the IOS on my phone I feel that would fix the issue since even my other phone has the same exact issue and they are both on 17.3.1.....

any recommendations or advice that I have not tried above would be amazing and TIA.