Just looking at your piping on this page and diagram you showed on page 2,it seems your piping is piped up wrong,like top exit of membrane = should be blue piping ( produce water ) and go in port 5 but you got black pipe going in port 3 and bottom exit point on membrane looks like using blue tubing instead of red ( waste water) and can see it exit membrane then go into a t then dissapears but then see another blue pipe going into port 1 when waste water should go into port 3.
So if I was you I would re- check all your pipework and make sure all correctly piped ( doesn't matter colour pipes you use for each stage of rodi but helps if all waste water,incoming water and filteted water all colour coded as easier for you to track pipes and also easier to read the tds whether you got dual,triple or quad tds reader)
Maybe your tubing is piped up correctly and your turned membrane upside down or I'm not tracing the piping correctly if so fair enough .
Also from your water report I read you get your water from 1- 3 Wells in your area on average ,I'm sure I've read other rodi problem threads and it's been mentioned excess c02 from well water and it had to be de- gassed.
Also pack in your di resin really tight
Anyway good luck ,just thought I'd point out what it looks like on your tubing