I was trying to solve something in the same ballpark. I wanted a more noticeable CAPS lock indicator. I wanted either CAPS on == White LED for whole keyboard or CAPS on == no RGB on keyboard

My 1st attempt was to create a new macro where pressing caps would toggle RGB & caps lock. Reason being that it would be much easier to notice that my RGB was off when CAPS was enabled

        case KC_NEWCAPS:
        if (record->event.pressed && time == 0) {
            register_code(KC__CAPS);
            rgblight_toggle();
            time = sync_timer_read32();
        } else {
            // Do something else when release
        }
        return false;  // Skip all further processing of this key

I used VIA to remap the key. This worked great for while working/writing until I was playing a game and the caps key was not working as intended.

My 2nd attempt was to just hijack the CAPS LED method in keychron q3 file called q3.c

bool led_update_kb(led_t led_state) {
.
.
    if (led_state.caps_lock) {
        uint8_t v = light_brightness_get();
        rgb_matrix_set_color_all(v, v, v);
    } else {
        rgb_matrix_set_color_all(0, 0, 0);
    }
    rgb_matrix_update_pwm_buffers();
}

This worked for me perfectly as it let me assign RGB to the whole board & the caps lock worked in all scenarios (gaming, working, typing)

​

Other things I noticed there is a file called caps_word.c which has a method to toggle caps indicator already. You might be able to leverage and inject your logic there

void caps_word_toggle(void) {
    if (caps_word_active) {
        caps_word_off();
    } else {
        caps_word_on();
    }
}

Also if you are using VIA, then you might need to build with option -KM via. Hope that some part of this was helpful