If you haven’t measured the resistance (with the power off) across the test points (1 and 2), please do that…just to ensure there is no short or near-short on those pins. There may be a short on a part of the board that isn’t visible.
To find out if the LDR is defective you can always measure the resistance across TP1 and TP2 (with the power off), while you shine a flashlight in the hole you made earlier in the heat shrink. I’ve never seen an LDR short out or go bad, so it’s probably not that.
-Brach