I like the idea! There's already a Voice Clip Sender script which "converts" Plus! sounds to voice clips, so why can't we do this for another kind of sound?
About the / or ! conflict, there have been some rules made about this. A / command is for the client side (like /prefs to open YOUR preferences), while ! commands are made to be used by your contacts. They will be sent to you and your script will recognize it. In this case, I think you can use both so both you and your contact can request it.
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