I'm confused on what exactly you're trying to do. You're measuring the resistance between the power side of the 15a cig lighter fuse and every wire on the vehicle? Power side of that fuse is fed right from the battery so you're basically measuring the resistance between the pos bat term and everything else which won't be of much help with this problem specifically. If testing from the fused side of the fuse you should only be showing a reading on what that fuse supplies, the cig lighter and obd port. A reading anywhere else is indicative of exposed wires touching.
I forget if it's been mentioned or not but have you removed the underhood fuse box and checked underneath? It's a spot loved by rodents and pests for nests, oh my!
If everything was copacetic before the starter was jankied with then most likely the starter, or something closely associated with it, needs a fine tooth comb treatment.
