I re-tested with the HTH kit and got the same weird result - the sample had a faint yellow tint after the 5 drops of hardness indicator (which is listed as 23% isopropanol and 77% Triethanolamine).

I tested with the PS234 and after 20 drops of cal 1 and 5 drops of cal 2, the sample was pink. After two drops of cal 3 the sample turned blue. This makes sense and is about what I would expect.

I then started over with 20 drops of cal 1, then 5 drops of the HTH indicator and the sample turned pink although deeper than with cal 2. I then tried the HTH titrant and after 10 drops it was more of a greyish color but nowhere near the blue from the last test. I repeated this test using cal 3 as the titrant this time and got the same grey result so it is clearly the HTH hardness indicator that is not working with my water for some reason.

I also tested pH (7.3) and alkality (90) on the sample.