Copy paste bug in xkmread.c
https://gitlab.freedesktop.org/xorg/xserver/-/blob/master/xkb/xkmread.c#L529-535
act->devval.device = wire.actionData[0];
act->devval.v1_what = wire.actionData[1];
act->devval.v1_ndx = wire.actionData[2];
act->devval.v1_value = wire.actionData[3];
act->devval.v2_what = wire.actionData[4];
act->devval.v2_ndx = wire.actionData[5];
act->devval.v2_what = wire.actionData[6];