Samsung Galaxy S8 (SM-G950FD) firmware issue - Android Q&A, Help & Troubleshooting

Hi,
I have a serious issue with my Samsung Galaxy S8, 64 GB, dual sim. My phone has stock android, never rooted, never modified in any way. I run it in Australia but got it from overseas. After a system update (sometime in December) my phone rebooted (precisely on 29/12/2019), and after the reboot it got stuck at the android logo. Typical boot loop issue, so far so good.
Immediately after, I managed to boot into recovery mode with the intention to wipe the cache partition or do a factory reset, but neither functions worked. In fact, not a single function in recovery mode works. I can scroll up and down and select any option, but without actually executing the functions. And on top of that, after a few seconds the recovery mode freezes and I can't do anything but restart.
The only useful info in recovery mode is the following (on the top part of the screen):
"Android Recovery
Samsung/dreamltexx/dreamlte
/PPR1.180610.011/G950FXXU6DSK9" (please note that "G950FXXU6DSK9" is what it says there now, after flashing this particular firmware - see below. But the error messages were the same even before flashing).
and below, in the output part of the screen:
"fail to open recovery_cause(No such file or directory)#
Reboot recovery cause is [UNKNOWN]
Support SINGLE-SKU
File-Based OTA
Supported API: 3
E: unknown volume for path [/odm]
E: unknown volume for path [/vendor]
verity verification failed...
E: [libfs_mgr]is_dt_compatible(): firmware info was not valid : '/proc/device-tree
/firmware/android/compatible : no such file or directory"
When I attempt a factory reset (or any other function in the recovery menu), I get the following error message:
"wiping data...
formatting /data...
formatting /cache...
data wipe complete.
E: [libfs_mgr]is_dt_compatible(): firmware info was not valid : '/proc/device-tree
/firmware/android/compatible : no such file or directory"
Apparently the firmware "G950FXXU6DSK9" doesn't work. So I got myself Odin (Odin3_v3.13.1) to flash a working firmware but cannot, for the life of me, figure out the right firmware - mostly because I don't know the right PDA and CSC.
In any case, here is the Odin log:
G950FXXU6DSK9_G950FOXM6DSK9_SMA
<OSM> Enter CS for MD5..
<OSM> Check MD5.. Do not unplug the cable..
<OSM> Please wait..
<OSM> Checking MD5 finished Sucessfully..
<OSM> Leave CS..
<OSM> Enter CS for MD5..
<OSM> Check MD5.. Do not unplug the cable..
<OSM> Please wait..
<OSM> Checking MD5 finished Sucessfully..
<OSM> Leave CS..
<OSM> Enter CS for MD5..
<OSM> Check MD5.. Do not unplug the cable..
<OSM> Please wait..
<OSM> Checking MD5 finished Sucessfully..
<OSM> Leave CS..
<OSM> Enter CS for MD5..
<OSM> Check MD5.. Do not unplug the cable..
<OSM> Please wait..
<OSM> Checking MD5 finished Sucessfully..
<OSM> Leave CS..
<ID:0/005> Odin engine v(ID:3.1301)..
<ID:0/005> File analysis..
<ID:0/005> Total Binary size: 5843 M
<ID:0/005> SetupConnection..
<ID:0/005> Initialzation..
<ID:0/005> Set PIT file..
<ID:0/005> DO NOT TURN OFF TARGET!!
<ID:0/005> Get PIT for mapping..
<ID:0/005> Firmware update start..
<ID:0/005> NAND Write Start!!
<ID:0/005> SingleDownload.
<ID:0/005> sboot.bin
<ID:0/005> param.bin
<ID:0/005> up_param.bin
<ID:0/005> cm.bin
<ID:0/005> boot.img
<ID:0/005> recovery.img
<ID:0/005> system.img
<ID:0/005> userdata.img
<ID:0/005> modem.bin
<ID:0/005> Transmission Complete..
<ID:0/005> Now Writing.. Please wait about 2 minutes
<ID:0/005> Receive Response from boot-loader
<ID:0/005> modem_debug.bin
<ID:0/005> Transmission Complete..
<ID:0/005> Now Writing.. Please wait about 2 minutes
<ID:0/005> Receive Response from boot-loader
<ID:0/005> cache.img
<ID:0/005> omr.img
<ID:0/005> RQT_CLOSE !!
<ID:0/005> RES OK !!
<ID:0/005> Removed!!
<ID:0/005> Remain Port .... 0
<OSM> All threads completed. (succeed 1 / failed 0)
Here is what I know:
- Model of my phone, as seen on the back of the phone case (SM-G950FD)
- region of my phone, as seen in the download mode (XSG - United Arab Emirates).
- my IMEI, as seen on the back of the phone case
- my phone serial number, as seen on the back of the phone case
- Chipset: Samsung Exynos 9 Octa 8895, obtained via IMEI.info
- OS: Android 7.0 Nougat, Android 8.0 Oreo, obtained via IMEI.info
- I can enter the download mode
- I can enter the recovery mode, but not do anything
Here is what I don't know:
- my exact PDA
- my CSC
- and therefore, my exact firmware
Here is what I have tried, unsuccessfully:
- used the most current version of Kies; however my device is not supported.
- used the most current version of Frija (v1.4.2); however I got "error 102. unable to find firmware"
- downloaded and successfully flashed 3 different firmware versions, obtained from sammobile.com. these 3 versions are:
G950FXXS6DSL2_G950FOXM6DSK9_BTU
G950FXXU6DSK9_G950FOXM6DSK9_BRI
G950FXXU6DSK9_G950FOXM6DSK9_SMA
I have flashed AP, BL, CP, and CSC. I did not flash HOME_CSC. Then I tried also with HOME_CSC, but no difference.
however after successful flashing, the outcome in recovery mode was unchanged. I still couldn't use any of the recovery mode functions, and I still got the exact same error messages.
I also tried flashing G950FXXS5DSI1_G950FOXM5DSHC_XSG, which at least had the correct country code (XSG), but this one I couldn't flash using Odin, so I went back to a previous one (G950FXXU6DSK9)
Does anyone have any idea what my error messages mean, and how to overcome them? Can anyone tell me the exact firmware I have to use to get this to work again?

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help
any ideas?