Your device is designated by Samsung as QN85A.
According to Samsung, the holder should be compatible:

Neo QLED/QLED TV
QN900 (65-85''), QN800A (65-85''), QN95A (55-85''), QN90A (50-85''), QN85A (55-85''), Q70A (55-85''), Q60A (43-85'')

Crystal UHD TV
AU9000 (43-85''), AU8000 (43-85'')

The Frame
LSO3A (43-85''). Slim Fit Wallmount is already included.

https://www.samsung.com/ch...

Secondo me le staffe che ho acquistato io per il mio tv neoQuled qn 65 800 atx, funzionano anche per il tuo modello da 75pollici.
Per essere sicuro al 100% ti consiglio di telefonare al supporto Samsung.ch.
Come ho fatto anche io per avere la conferma che andassero bene le staffe.
Saluti Moreno
In my opinion, the brackets I bought for my neoQuled qn 65 800 atx tv will also work for your 75 inch model.
To be 100% sure, I recommend you call Samsung.ch support.
As I did to confirm that the stirrups were ok.
Regards Moreno