I think your instructor needs to get a few facts straight.
I don't know Leigh Childs or train with any of his schools but I know of him from years back.
Childs used to be TAGB, which is probably why your instructor is (apparently) bad mouthing.
About 14 nyears ago the TAGB split from master Hee Il Cho and a group of senior instructors decided to go with the Cho, rather than the TAGB. These included guys like Kim Stones, Tony Sewell (both world champions under TAGB) Frank Murphy, Ted Hopwood (at the time about 7th dan, one of highest dans in UK), Mark Weir (yes, the MMA guy)and Clive Harrison. This group became GTI (Global TKD International).
Leigh Childs was part of the group. I believe he was 2nd dan at the time (although I could be wrong)but he certainly did not start up his own group at this time (that seems to have happened much later). I don't see how a red tag would be able to start his own group amongst the above mentioned BB's.
I remember using a video of Childs Chang Hon patterns to get ready for black tag gradings and Clive Harrison was speaking on ithttp://www.shopireland.ie/dvd/reviews/B00005RHJJ/2/
Since then I know he was involved with professional MA schools and worked with John Jepson (karate) for a while. Likewise, I don't see how a red belt could work with someone of Jepson's reputation.
I checked out his website and it looks like he's made a bob or two, but I'd question his claim about bringing 'professional MA schools' to Britain's shores.
As for weapons, why not. It is a part of TKD which is lacking for many people. Would you think of ground work in the same way?
Prices? No idea... caveat emptor.