Any of these can be used as suggestions to the devs, and I urge you to suggest things for Madexx as much as possible considering how hard he is to camp in his current location (quest area, farming route, and dig site area). (You make suggestions by clicking Ctrl-right clicking or something on the mob... it will tell you the right keys when you mouse over them and can be done on dead mobs too)
Request/Suggestion #1: Is it possible to try and see if Madexx's spawn time has been set to a lower timeframe. For example, instead of his 6-24hr spawn has it been lowered to 3hr-6hr or 4hr-8hr, etc... Also... is (or make) his spawn time more consistent? Like instead of spawning one time at the 6hr mark and then the next spawn is 24hrs later.
Request/Suggestion #2: Make Madexx harder to solo for one person. Give him some skill (kinda like Nerf Bat) and more health so it will make it much harder for some people to solo him, so if someone does attack him they will actually have to fight for their lives.
Request/Suggestion #3: I know this one will upset some people, but in the end it actually might be better for everyone... Make the non-rare Madexx-skin mobs one color and not color changers, while making Madexx NOT spawn in that one color any longer, and the people who have tamed him already in that color would either get a new color (or highlights/markings), or get one of the other 4 colors at random. I would suggest that the bronze/brown one be made into the normal mob since that is a more realistic scorpion color. (And before I get called out for this... I have the brown Madexx and I don't have a problem with this.)
Request/Suggestion #4: Make the non-rare Madexx-skin mobs a totally new color, but make the actual Madexx camp somehow less stressful (see suggestion #1, #2, and #5).
Request/Suggestion #5: Suggest that Madexx should be made into a spawned/phased quest-related mob that will spawn after an item is used and depending on the item used (five different items could be used... one for each color) Madexx would spawn in a specific color. Easy tame and quest could be completed once, but hunters could easily not turn in the quest and have the ability to go and get whichever color they want at any given time... while other classes would still get rewarded for doing the quest.
Request/Suggestion #6: This is a kind of a silly suggestion.... Either make a Madexx barbershop where his color can be changed for a modest fee... like 500g, OR a quest where it can get dyed to one of the other colors.

I encourage everyone on the PTR to make any of the above suggestions. You can make the Madexx suggestions even if you don't see Madexx by submitting the suggestion(s) by clicking on the non-rare Madexx skinned mobs and doing it there. It doesn't have to be suggested onto the actual mob, it just has to be suggested so the devs can see it.
If any of you have other suggestions that are Madexx related please feel free to post them here. I am going to keep trying to get onto the PTR and when/if I do I am going to come back here and see what I typed and what others typed. This thread will be like a notepad for suggestions.
My reasoning behind this thread:
(This Thread is for Madexx related PTR suggestions. I feel the need to suggest these because I feel that Madexx is probably the hardest camp to endure as a hunter. I camped Aotona for 7 weeks (about 1.5 years ago) and I never felt like I was not going to ever see Aotona... Aotona spawns in a heavily farmed area and I still felt like I had a chance. I feel completely different with the Madexx camp... it might just be my server, but I really don't feel like me or anyone else will ever tame Madexx (again... to get the specific color I/they want) without him spawning right in front of the hunter, because one loop around his spawn points and missing him means he'll be dead by the time you get back around.... even at 2am. The Madexx camp has way too much RNG going for it and going against us hunters... hence the reason why I am only doing this for Madexx and not the other new Cataclysm [hunter tameable] rares.)