Are there any log entries in openhab.log when your rule is triggered?
When all is OK, you should see something like this:
executed commandLine '/etc/openhab2/scripts/fire-control.sh 85'
If entries like that are there, maybe i would start with with a command that is easier to track. Like start a stream and use keyevent 85 to pause the stream.
BTW here is the script “fire-control.sh” i use that can be fed parameters:
#!/bin/bash
#works without next line, dunno what it's good for
#adb tcpip 5555
adb connect YOUR-FIRETV-IP-OR-DNSNAME-HERE:5555
adb shell input keyevent $1
adb disconnect
can be called like so with any keycode you fancy:
executeCommandLine("/etc/openhab2/scripts/fire-control.sh 85")//85=code for play/pause