I will try and keep it to the OPs boat and your two points.
How would this tool take to identify which item is the vampire? If relying on the tool to identify energy and name the source of energy consumption it varies greatly. My system has yet to identify a single light, the boiler, the central heat fan, ceiling fan, nor a TV/cell phone/desktop computer/laptop/game console after 2 years. It took a year to identify my oven. It took 18 months to identify my induction cooktop (well some burners, but that is to the next point). In fairness, more common things, like the well pump, showed up after the first couple weeks. In addition it doesn't always identify a device as we think of if, often you get vague things like "motor" "heat" or "A/C" followed by a number (it can be somewhat helpful as often it does provide the top few things that similar power signatures have been identified as by the community) and sometimes they need to be merged; for example I think my heat pump water heater showed up as all three of those and I merged them, sometimes after many more months it will do it on its own (though it will also merge devices that are clearly separate which you have named and provided model numbers for). In addition there is a column (well bubble) for "always on" which goes up and down constantly, as I understand it the sense identifies items based on their energy draw at start up, so an always on vampire load would be a challenge for the system. As I understand it, sense ID items via AI and community feedback as to what those items are, so if you have less common items (in my mind things like heat pump dryer, induction cooktop, or hybrid water heater) you may be waiting a long time. So far I have not found a way to "train" it; I would love to be able to tell it I am going to go turn the basement lights on and off 20 times watch for that.
After 2 years ~66% for my usage is still "other" and ~22% is "always on" (despite the name this reading varying anywhere from less than 100w to reading almost 1,200 watts).
As for history. The only easy (really only, but that could be user error) history I have found is for devices that it has identified. Those give a estimated cost in dollars and percent of monthly use, a bar graph of usage by day/week/month/year/bill, total usage, total estimated cost, times on, and total time on. I find this history suspect for two reason and I will give an example of each. It does not detect every time a device turns on; it has identified our EV, but at least once a week our EV charging is "other" not "car's name". And in the opposite direction it has identified our well pump, which it thinks runs in the middle of the night hours after we have gone to bed; I thought we might have a leak based on that and turned the breaker for the pump off overnight and still say the pump run. Both under and over reporting makes history suspect.
In sense's support I have read stories about people reaching out to customer service and getting knowledgeable responses and assistance. And Amazon is full of great reviews. My experience is that it under delivers compared to what my expectations were, is not the most reliable, and requires a good bit of involvement from the user.
For the OP's case for searching for a load in a timely manner and if I had exposed wiring in the basement/at the main panel I would much prefer a clamp style meter to quickly show the consumption of each wire and hunt down what is on that circuit.