When racking after primary fermentation, I did a taste test and thought there wasn't any noticeable caramel flavor. So I bought another two 8 oz cans of fat free condensed milk, boiled them for 6 hours, mixed into one to one parts boiling water, brought to room temp, then added to carboy. Primary was reinvigorated for maybe a day. After another week I racked and tasted. Still lacking the 'caramel apple' profile I was wanting. I've since decided to take the cider in a new direction. It's nearing applewine now with a 10% abv and is crystal clear with a nice red hue. I've been soaking american oak cubes in Lagavulin 16yr. These will go into the carboy for another two weeks of so to integrate a smokey woody taste, I hope the remnants of the dulce profile will compliment these more assertive flavors.
I think the issue has been fully integrating the dulche. Both times despite diluting to similar fluid consistencies and vigorous shaking of the carboy, the dulce seems to find a way to settle to the bottom. When I attempt again in the future, I'll add the dulche at the end of the wort boil.