Another Stupid Battery Question

[Down South]

I bought a 2012 cart upgraded by CC in 2015. It was abused as far as battery maintenance.
It has 6-8V Trojan batteries all dated L4 which translates to 12/14 when they left the factory. The time from factory to cart, I don't know.
When I got the cart, four batteries were dry. It took almost 2 gallons of distilled water to get those 4 batteries with water just over the plates.
The other 2 batteries had water over the plates, both drivers side batteries.

Now, this is what's strange to me and some of you can probable explain it.
The 2 batteries that had fluid over the plates test bad. I've let them charge with the pack several times, reset the OBC & let charge several times. They are just bad. The voltage after charging & 12 hr rest on these two batteries is 8.3V +- .04V.

The other 4 batteries that were dry test good at 8.56V after charge and 12 hr rest.
The sides of a couple of these 4 batteries are starting to bulge slightly, probably from overcharging I'd guess.
These 4 batteries have a good SG reading on every cell.

Now after all of this, my question.
Do you think it would be best to purchase two new batteries from Sam's or Costco to replace the two bad batteries and try to push the pack for another year or two or just throw my hands up and purchase a new pack?
When I do replace the pack, I plan to go back with Trojan and they are $145 plus tax each here.