But in any case CO2 isn't what's narcing you - it's nitrogen. CO2 isn't supposed to be part of the equation.
CO2 does not cause narcosis. I don't know who the "experts" are you mention but they are not remotely expert. There is no significant amount of CO2 in compressed breathing gasses, it is an issue on rebreathers where the diver re-uses their exhaust gas. There is more Argon than CO2 in atmospheric air and that is very narcotic.
Composition of Air
According to DAN's Deeper Into Diving, 2nd Edition, pg 113, written by John Lippmann and Simon Mitchell, "Hypercapnia does appear to increase the narcotic effects of nitrogen. The depressive effects of both CO2 and nitrogen, as well as the increased delivery of nitrogen, combine to increase narcosis."
Also, CO2 is a factor in open circuit diving due to gas density and work of breathing. Hypercapnia is the buildup of CO2 in the body due to insufficient ventilation. Ventilation is impeded by depth (at 100ft work of breathing is twice that on the surface), the inherent resistance of your breathing apparatus, and gas density. All of these, in addition to increased work at depth causing increased production of CO2, contribute to hypercapnia.
On top of that, some people are naturally CO2 retainers, and so a rise in arterial CO2 levels does not stimulate a corresponding rise in ventilation as it does with most people. This is not good.
So, to answer your question, if you regularly experience narcosis at 130 feet, without doing significant work at that depth and assuming your equipment is functioning properly, trimix should improve the situation. The benefits grow as you go deeper, not only from the displacement of nitrogen, but also from the gas density which affects CO2 retention and work of breathing.
And yes, if you're experiencing hypercapnia to a significant degree, it's an issue whether you have helium or nitrogen in your breathing gas. But, depending on the circumstances, switching to helium may not make any difference. For example, if you're shallow and experiencing hypercapnia and feelings of narcosis because you're working hard against a current at 80 ft, it's most likely the work that's causing the problem, not your breathing gas.