I think a bug is certainly possible but I'm not buying the visiting nurse or hospice worker, unless these women have serious dementia. If they are that disabled, I doubt they would be living alone.
Think about it, a woman would have her glasses on when a male nurse visited. She would most likely talk his ear off and get to know him a bit. She's going to relay that to LE when they question her about the rape. "Well, there was this nice young black man who came by last week from ABC Home Health Care. He really admired my old clock. But he was a nice man."
They'd be on that in a flash. Plus, I think there's nothing wrong with these ladies' other senses. I imagine they'd automatically sense if they've been in the presence of their rapist before. They'd recognize voice, smell, etc. They might not be able to exactly place where they've seen the man but I think they'd relate to LE that he seemed "somehow familiar".
I think that LE has most definitely already looked at any possible service scenarios in each of these cases. They are most likely not only talking to the women but to their families. Oftentimes, families will arrange for service people for their elders. Neighbors would have been questioned at length--tree cutting, surveying, new gutters, deliveries, etc.?
We, including LE, haven't found the missing piece of the puzzle yet. I honestly don't think that LE is holding back. They'd be issuing specific alerts if this was thought to be related to a service industry.
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