ok I found the culprit and it might have been a combination of things but I got it to work
Wanted to upgrade site from php7 to php8.1 PLUS upgrade from modx 2.8.3 to 3.0.1
After upgrade everything died, I first thought its getImage, then I thought, its cache or a PHP 7 - 8 issue.
1st problem getImage had was parsing HTML that strange enough worked in php 7 but in php 8 did not parse and I got a white blank screen.
Hence I removed the richtext plugin in migx and change it to a plaintext that is getting cleaned with an output modifier.
Secondly I had way to many bad conditional statements esp if then. According to this great article by jason Tags as the Result or How Conditionals are like Mosquitoes | MODX
I fixed them all and changed them from
[[*field:is=1:then=[[!SomeScript]]:else=[[$SomeChunk]]]]
to this
[[[[*field:is=1:then=!SomeScript:else=$SomeChunk]]]]
this especially got rid of many errors in the template chunk of the nested getImage MIGX
I also applied this fix by joshua that might have fixed more output filter issues
now its working but had to rewrite alot of stuff
thanks for the help everyone