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I've tried for ever to do this challenge without looking at a guide I'm at 7/10 and I believe they're invisible just what the hell, I'll get around to it some time with a video guide I've done everything else I hope mine is not bugged also.
At least one of the mines does NOT highlight in Survival Instinct mode because it's too far away from you and you can't get any closer to it. It's the one to the west of the shipwreck where you find the pulleys. You'll just have to look for it. If it's dark, it'll be difficult to see as well.