I still like c/c especially since he minbet it I think.
Why? You must start to think through things like this enty. Why do you think c/c is a good idea?
The basis behind c/c is this. Villain MUST have a high bluffing frequency and we must have a reasonable expectation that villain will bet river (in this case) when checked to. Related to this is the fact that we typically need villain to have a wide preflop and flop peeling range - because if this is the case villain will have alot of air hands and if we reasonably expect villain to bluff with a decent portion of these then villain's range is heavily weighted towards bluffs when he bets river.
Another reason might be if we think metagame is such that villain can value bet us very light, but might not call down as light (very rare that this would happen - you'd need to be a bad loose passive in villain's eyes). So in this case villain might vbet 9K thinking he can get called down by a worse 9 and a 7, but if you bet you almost always have an A or 2 pair so villain will fold. But you don't encounter thinking players at nl25 so don't worry about this last one.
So, we have to consider 2 things on the river. Villain's range for betting the river and villain's range for calling the river. Villain's range for betting the river here will be 2 pair + hands and bluffs - and almost never anything else. This kinda villain isn't going to vbet a nine on the river nor is villain likely to turn a hand like K4 into a bluff. So frankly we might as well be calling down with a 7 on this river, since a 7 is going to beat as many of villain's bluffs as will AJ. So the only time c/c can be good is if villain will bluff river alot or turn some of his weak made hands into a bluff (like K4 realising it probably isn't good - but again this villain won't do that). Where AJ>>>>>>>>>>>7x is when it comes to villain's river calling range. You can't vbet a weak 7 on this board, but you can vbet AJ and get called down by 9x and sometimes 7x.
So in this case villain's river calling range probably is much wider than villain's river betting range, since weak made hands check behind so we have a polarized 2 pair or better + bluffs range --> and when villain probably doesn't have that many bluffs in his range (and lets face it we have ABSOLUTELY NO idea about villain's river bluffing frequencies at this stage so it is a blind guess at best) c/c is just so bad.
I think i know why you like c/c. You want to see showdown and you don't want to have to fold to a river raise. But who cares? If he raises this river he almost always rivered 2 pair so it is an easy fold knowing you aren't ahead. You absolutely must be looking to extract the most value, not just getting to showdown by all means necessary even if it means that you take a bad line (c/c) that will never be good vs villain's vbetting range and you might as well be snapping off whatever portion of villain's range is a bluff with a much worse hand. You are turning your strong AJ into 32 for all intensive purposes by choosing to c/c (except in the cases where villain has a worse A high on the turn for some reason).
But honestly enty read this until you understand it because it is extremely important to understand.