Jose,
I would approach this in two ways depending on what’s being triggered. Ideally cues can be triggered directly by receiving an LTC time code signal. In that case I would make a time code output from QLab that triggers at the same time by using a timeline group. Then send that signal out an analog output and DA the signal to as many destinations as needed. If you have time code readers you can place those around to positions that don’t receive time code for automatic cue triggering.
The other option is to make a low res version of the video with a burnt in time code window using non-linear video editing software for example- Apple Final Cut Pro or Adobe Premier. Then lay that video into a timeline cue that triggers at the same time as your primary video. Send that video to an independant video output that feeds as many displays as you need via HDMI or SDI DA’s.
For reliability I would stay away from anything the requires too much IT/tech.