Ok, this seems to be two separate questions so that's how I'm approaching it. My advice is only anecdotal from my own experience and doesn't purport to be some absolutely correct answer.
I have used the oven method for fermentation a few times and have had no discernible problem with it. I have not used a pH meter so I can't know absolutely but the taste was right and there was no undesirable bacteria growth so that's good enough for me.
I have in the past had the same issues using the salt solution; it doesn't keep humidity high enough. Beyond that it's also a mess and a pain to make and maintain. It also takes much more monitoring and work to maintain the humidity. If your chamber is big enough (full refrigerator size) I would use a regular room humidifier with a hygrometer and auto humidity control. I use this one.
I say you need to have a larger chamber so that there is a bit of room for circulation and so the water is not accumulating on the meat and because the unit is rather large. This can probably be worked around by using a smaller unit and one like this that really makes a fine, light vapor.
I guess what I don't understand is why you would need to invest in "another RH controller and humidifier." If you have one, why do you need to use the salt solution?
An alternative suggestion: I bought this humidifier for my chamber. It has an attached hygrometer and will in theory shut off and turn on the unit to keep a set humidity. I haven't set it up and started using it yet so I can't vouch for its effectiveness but it would be much easier and cheaper all around to use this. It also has a larger basin, which will save you effort. If you can return the one you bought then I would just get this one and try it out.
shoot okay, i just ordered this guy, if it doesnt work might have to do what you did as well
you can buy a controllable humidifier off Amazon: http://www.amazon.com/gp/product/B000O3I2BC?psc=1&redirect=true&ref_=oh_aui_detailpage_o00_s00 this worked for me for about 5 months, then i had to switch due to a sensor issue