Review on 🚗 KONNWEI KW600 Car Battery Tester: Professional 12V Load Analyzer, Alternator Tester, and Voltage Test for Automotive Batteries by Rob Bradford

I like how this battery tester/reader works, but I have an issue I'm not sure about yet. When I mount a battery reader to lead posts, I get higher (better) readings than when I mount them to threaded steel posts. My question is the reader or the battery. I have brand new (1/21) and (11/20) 12V Deep Cell Marine batteries for my RV and am getting SOH 88% (low), SOC 98% with 4.50 resistance readings on lead terminals MOhm. VOM shows 13.28 volts (same on both posts) and reads "Good Battery". On steel threaded rods. I get SOH 46%, SOC 98%, 8.57 MΩ and prompts me to "replace" the battery. I also have a new battery dated November 20th with HOC 84% (low), SOC 98%, resistance at 4.75 µs and VOM reading of 13.33 volts on both the lead and steel terminals and reads "Repeated Charge Test". . I get 71% SOH, 98% SOC and 5.57 MΩ resistance. and reads "replace". These batteries have never been installed and were purchased on January 25, 2021. What's happening?