Filter Forwarded Plugin Profile Message?

Using Vera Alerts and the Android app, there is an issue with validating alerts that have been delayed for any reason as the timestamp is set to the app’s reception time. To mitigate this, I use the {timestamp} variable so that I get the correct timestamp of when the Alert was generated, rather than the received time on the app. This works just fine.

My question or problem arises when I try to feed the same message to Sonos, using the Forwarded Plugin Profile, which then speaks the timestamp in an undesirable way. The question is: is there a means of filtering the {timestamp} variable out of the Sonos Say {Message} command or is creating alternate notifications, without undesired variables the only or better course.