If they have reduced red perception they may be able to see other colors but I would expect that far red would be too faint.
If they just lack the L cones that discriminate between green and red they won’t be able to see it at all or at least have big issues seeing it. If you trust the Wikipedia graph, M cone sensitivity pretty much goes to 0 at 660nm and beyond.
OTOH IIRC someone (you?) in this thread have said that they can tell apart 660nm and 730nm by color. The cones can’t detect wavelength directly, the color perception comes from the difference between each cone signal. If the signal from the M cones is already at zero you shouldn’t be able to tell the two wavelength apart, unless you have 4 types of cones (the extra cone is between M and L cones). Of course it could just be ambient light messing with the color perception.