If the fish are willing to breed they are mature enough, regardless of age. The only reason for growing a fish out to 6 months is to allow it to get it's full finnage which is not necessary for breeding anyways.
He does have a heater in one tank. Not necessarily an acceptable heater but he does have one. There are some breeders of the opinion that conditioning is best done around 76-77*F in which case that heater may be keeping the temperature at a decent range. Another option would be to heat the room and not the tanks. Just because the room is dark doesn't mean its necessarily cold.
I've already address the problems with the OP's set up. So obviously I'm not saying he is doing things correctly. I am, however, providing useful information instead of having yet another bash the OP thread. But no, those 6 or so threads in the past that turned into 6 pages of how much everyone hates the OP turned out so well
How does that look to new members or guests? They don't know the history of this member.. they just see someone asking a question and getting bashed.
Just because something is not being done how you would do it doesn't necessarily make it wrong. There's no evidence proving a hide makes bettas more comfortable or healthier. In my experience my fish NEVER use their hides so I got rid of them.. it's a waste of my time to provide hides and have to remove them and prolong water changes.
But since my replies obviously were saying great job OP I'll rephrase.
First, You need to provide BOTH fish with at least 1 gallon containers that are full of clean, dechlorinated water. These containers need to be heated to AT LEAST 76*F, IMO 78* is best. NO EXCEPTIONS on the temperature rule.
Second, You need to change 100% of the water daily, replacing it with clean, dechlorinated water. It's up to you whether you age your water or not. I do not age my water but there are benefits to doing so. NO EXCEPTIONS on the water change rule.
Third, You need to feed your fish at least 2 times a day. I try to feed mine 3 times a day. You need to feed a mixture of high quality foods. The foods I use to condition are: Atison's Betta Pro pellets, Frozen Bloodworms, Frozen Daphnia, Frozen Brine Shrimp, Frozen Glass worms, Live White worms, and NLS Growth Formula pellets. Not feeding enough foods and only feeding 1 or 2 foods will not get your fish into condition.
Fourth, You need to continue this regime for AT LEAST 2 weeks. NO EXCEPTIONS. Each part is equally as important as the next, you can't skip one part and hope that they'll still be conditioned.
If you feel your female is stressed from shipping give her an extra week of conditioning to get her into shape.
Conditioning is by far the easiest part of spawning. Honestly if you can't even handle that I really don't think your cut out for breeding.