Although HOV lanes are highly useful in this very congested area, combination toll-road HOV operations simply don't compute.
We've always had this problem with VOT. They envision Virginia as consisting mostly of open country with natural corridors controlled by mountain ranges. Northern Virginia is the other way around ~ it's not been open country for many years, and the natural corridors are controlled by the concussion rings put in place by a major meteor strike millions of years ago.
If the new toll-road HOV operation were to be made up of entirely new pavement along a new route, it might make sense and could even attract some traffic ~ if the drivers could get to it, which they can't because we do not have a secondary road "system" in this area.
You must be under the mistaken notion that there is no Federal money in your roads. There is always Federal money in "Interstate" roads.