Are you sure it's not just a by product of the colour?
Even the new acetech units state (from the manufacturer) that they are only compatible with green but I've literally seen them used and there are multiple independent (user) reviews that state they work just fine including earlier in this very thread. They are not quite as bright as green, hence I queried how bright they got earlier in the thread, but still.
My main point was regarding the use of huge bold black lettering saying DONT USE RED like it would cause harm to the tracer unit. Which it obviously won't.