Hi bheard. I can’t speak to the first part of your post but with respect to Richard Lake, the  roads you’re referencing  are ATV trails. Definitely not passable even in a 4x4 truck.

I went out to Boot last summer.  Jeff's map clarified the portage locations.  The Raja to Muskrat one was longer, but well marked & cleared.  The Muskrat end of that one was harder to locate on the return, since the sign had fallen. I missed it at first but luckily there was a large dam just a bit past it which I knew i hadn't gone over on the way out.  Muskrat to Bailey, and Bailey to Boot were shorter but rough & not well maintained.  I didn't go out to Richard due to my schedule.  The worst carry on the whole thing was the carry from Mole out to Raja: quite rough, with one esp. dicey bit where it went sidehill across a muddy slope with a drop to the creek, and then turned steeply uphill.  Raja was nice, except that as far as I could discover, there was no pit toilet. 

Thanks for the info…
Partly from replies here, I think I’ve cobbled together that the route to Boot must have been cleared somewhere around 2019-2020ish.

Besides your collective input, I found a video trip report by Matt Haughn — https://youtu.be/YNkI2Ylw740?si=Ef_4bhy2t4FELYPY
He made it.
I also found one from about 2018ish which was successful but only because they were clearly incredibly determined.

I’ve pencilled it in for this September or October.
I’ll update afterwards.