I am really confused, as every post in the forum regarding this issue talks about one of the options I have already tried, but I am still having this issue.
Yes, if you can show the properties of RG so we have better understanding but you can also add an action > Element Actions > Display List in RG to display the DB values by using the Do a search for when the button is clicked.
It seems you have a constraint based on an input value for the repeating group then you need to follow that suggestion of showing the Display List when the input value is changed.