Hi

Märklin Sound locomotives are locked, meaning you cannot change the sounds
On the other hand Märklin mSD2 and mSD3 decoders can be sound edited to add either Märklin sounds or yours: This is the mDecoderTool3 (free) which may be downloaded from Märklin website (https://www.maerklin.de/)
Another avenue is since you have a CS2, you can play your own sounds using active loudspeakers plugged on your CS2 (passive loudspeakers won't work.

Because I am using Rocrail, I have created "Actions" (in the Rocrail meaning) to play various sounds from my computer. These include Bells and coal loading.
Now I need to add a speaker near my depot and my church.
Cheers
Jean

or Marklin ...

Use an ordinary sound decoder loaded with appropriate announcements but instead of installing it in a loco fit it and the speaker into the station building.

I don't know what storage space the Zimo one has, but both Loksound and Marklin ones have large amounts of space for sound storage. In addition because you don't need space for standard loco sounds you will be able to have an extra announcement or two.

Make each announcement triggered by a seperate function. The ESU decoders have some form of 'shift' function which can make sounds do different things when a function is set. I haven't had occasion to try this, so cannot advise further on it.