crashed validation/failed validation on NI plugins after update

 I’ve recently updated my system from 10.15.7 Catalina  to Seqouia 15.3.2. I’m on an Intel machine. However I can't seem to get my NI products working in Logic:

 - When opening Logic, of course the audio-units had to be scanned again, however the Auvaltool quit unexpectedly during scan (a couple of times)

 - In the Plug-in Manager, NI plugins are also shown as ‘crashed validation’ including Kontakt  7 & 8. Kontakt (6) is shown as ‘couldn’t be opened’ I use Kontakt on a daily basis for work so that's a bit of a problem.

• it's worth noticing all other plugins from other developers seem to work fine (Omnisphere Serum Sine Soundpaint etc etc)

WHAT I TRIED SO FAR:

  - I’ve tried installing the latest version of Logic, 11.1.2

 - I’ve tried updating & re-installing the plugins with the latest version of Native Access (the effects, Kontakt, etc), without success

- opening Kontakt standalone did work

 - The ‘reset & rescan selection’ didn’t work on any of the NI plugins. When I tried I got the popup ‘auvatool quit unexpectedly’ popups again. 

The validation report on for example just Kontakt 8 shows as follows (I could provide the reports on all plugins if that helps):

validating Audio Unit Kontakt 8 by Native Instruments:

    AU Validation Tool

    Version: 1.10.0 

    Copyright 2003-2019, Apple Inc. All Rights Reserved.

    Specify -h (-help) for command options

--------------------------------------------------

VALIDATING AUDIO UNIT: 'aumu' - 'NiK8' - '-NI-'

--------------------------------------------------

Manufacturer String: Native Instruments

AudioUnit Name: Kontakt 8

Component Version: 8.0.1 (0x80001)

* * PASS

--------------------------------------------------

TESTING OPEN TIMES:

COLD:

[2025-04-01 12:27:37.088] [info] initializing... 2025-04-01 12:27:37

[2025-04-01 12:27:38.388] [info] initialisation complete: 2025-04-01 12:27:38

FATAL ERROR: OpenAComponent: result: -1,0xFFFFFFFF

validation result: crashed validation

 - Maybe most importantly, I’ve tried following the instructions using this article:

https://support.native-instruments.com/hc/en-us/articles/360014454117-My-Native-Instruments-Plug-in-Fails-Validation-in-Logic-Pro

So that means I’ve granted Full Disk Access to Logic, Native Access, Kontakt, etc, as well as deleting the files from the locations described in step 4.

I gave this 2 tries, but this doesn’t work either; after the instruction of the re-start I opened logic once again, during scanning of the plugins, I got a the same couple (4) popups that the auvaltool quit unexpectedly. The same result as before as well in the plug-in manager.I’ve made sure to save the rapports on this with the details on what happened, which I can put in a mail if that helps.

Ofcourse, as I deleted the files from step 4, opening Kontakt in standalone right now doesn’t work either but it would after a re-install (which is what I did the 1st time I tried following the step 4). 

Any help would be very much appreciated as I need at least Kontakt to work properly for my daily job as a composer.

Many thanks,

Gijs