I know whats going on because I went through the same thing.
There are at least 3 different kinds of quick disconnect and they dont play with one another. You have a combination that connects but doesn't allow flow. So your half way there!
The difference is the size of the hole in the end of the male end of the QD. It's too big. To verify, connect the hose and then, using the collar on the female coupler, release the hose. If it shoots away from the coupler then it shold be working and something else is wrong. If it just stays in the coupler then the hole in the end of the male end is too big. You have to change either side of the quick disconnect or do what I did and install a 1/4" X 1/4" bushing into the end of the male fitting. This will push on the valve inside the female coupler and allow flow.
Hopefully this is whats going on; is the hole in your brass end the same size as the one shown in this pic? If so it needs to be the size of the silver hole in order to activate a valve inside the female coupler.
I found the aluminum bushing at the local H/W store in their Hillman selection. It's a standard size. I simply pushed it into the end and slightly distorted the brass to hold it.
It's all perfectly safe (worst thing that could happen is the bushing fall out and the gas doesn't flow but never has) and works great! I run a BBQ and fire pit through 25' on line.