If the brake squeal is part of the installed sound project, then you should be able to get it to play.
Not sure if you will be able to access this informative thread without being a member of the group. It talks about independent brake and also automatic squeal.
https://groups.io/g/Loksound/topic/88069105 . I also highly recommend joining that Loksound group. There are many knowledgeable members there willing to help (including several TRW members).
Here is an excerpt from that thread:
From the LokSound 5 manual:
13.4. Adjusting the braking sound threshold
The LokSound decoder is able to play a wheel-synchron brake
sound. To play a brake sound, Damit das Bremsgeräusch abge-
spielt wird, there are several conditions necessary:
•The braking time in CV 4 is set sufficiently high (at least value 20
or higher).
•The loco drives with high speed at the time of the braking com-
mand.
•The loco receives the driving command “Speed step 0”.
The LokSound decoder will now start to play the braking sound at
the time determined in CV 64. The higher the value in CV 64 is,
the sooner the braking sound will be played. The default value 100
is approximately equivalent to speed step 48 of 128.
The braking sound should and when the loco stopps. You are able
to do some “finetuning” with CV 65, if the loco stopps too early.