Looking at your Spectros, Puerto Rico was orange during the SI and Haiti quakes.
Looking at Volcano Discovery archive showed only small stuff.
https://www.volcanodiscovery.com/earthquakes/puertorico/archive/2021-08-20-2021-08-22.html
Different filters result in some base colors other than blue, and some stations are on a regular timed calibration or in error mode. The South Sandwich events that day are easier to target on nearby station’s propagation as the p and s waves spread. I didn’t mention that in the same video is a large 6.9 Alaska and a 7.2 Haiti quake. Thanks for your comments