I won't post pictures, because it will get people upset.
It's a funny one....although the area you are talking about was included in Wheal Agar, the more shallow workings are on 2 totally different adit systems and are more commonly referred to as Wheal Fortune and Wheal Tehidy. You have East Pool on the Crofty Adit system and that runs all the way to Robartes Shaft (Agar) in Morrison's car park. At depth, Agar runs into Fortune (same structures) and on into Tehidy. The latter two are on the "barncoose" adit.
The DLG stuff was quite well documented by Cornwall Archaeological Unit and their research is pretty thorough. You can find copies of it in the Cornwall Studies Library (out the back).
I have copies of the stuff here, and the document you are looking for is titled Tolskithey and is in their 622, 623 boxes "out the back". They don't talk about the shafts you refer to directly, but they do lots of other ones.
Like so many of Cornwall's building and ind-est sites, people are really not bothered about archaeology and things which hold them up. Very few of them have any sort of interest and it's not surprising to read in the CAU reports that when their man had turned up, the contractors had already destroyed the base of engine houses, and started capping, etc. Since the DLG book doesn't refer to the exact shafts you are talking about, it is probable they were plugged/capped before. If they are on private property (and that property hasn't changed hands recently) the state of the shaft plugs are of no-ones concern....unless there is a lender involved, and then they'd be out drilling holes in it....if it was under a property, or proposed property!
It is possible to get "under" all of that via the barncoose adit (which is locked and exceedingly difficult to find). It is a gruelling trip in ancient pokey tunnels which are almost flooded. Barncoose engine shaft still has the pitwork in it and there is very little to see apart from more and more and more poky tunnels and occasionally, you get to stand up in an adit shaft and give your back a rest. All of those shafts you are talking about are open underground and connect to the adit running towards the batcastled shaft in Wheal Fortune Park...the shaft station of which is filled up with porno mags and leaflets.
I'd go in Cornwall Studies Library and ask to see the "shaft capping contracts". 622/623 and in one of those is the Tolskithey folder. If you walk to the far corner (away from the door you came in by) there are some white ring-bound folders which are to do with the Baseresult activity at Crofty. In one of these is a whopper of an adit plan all folded up. There is also a report on the adit system from about 1998, which is also interesting reading and relevant.
By far and away the most interesting part of the area is the written history. The surface stuff has largely been obliterated and the underground stuff is torturous and not really worth the pain to visit....plus it's very locked and crofty get very upset with intruders (insurance, etc)