Single outlet and light set getting power from neighbors meter

We live in a town home that has one party wall. HOA stipulates repairs to party walls must be shared by owners of adjoined walls. We're remodeling the home to likely sell soon and have had electrical upgraded by a licensed electricians. I'm not an electrician but I'm comfortable doing lower level electrical work. House was purchased as is about 3-4 years ago.

In bringing our kitchen electrical up to code with GFCI protection, I've discovered one outlet that is our most used outlet in the kitchen which also powers our under cabinet lights and garbage disposal is actually fed from the neighbor's house and meter. The neighbor is the HOA treasurer and has (successfully) resisted any updating to our home that might require HOA approval. She is old and paranoid and believes any attempt to improve our property is a conspiracy to make her property look worse. She will absolutely take any notification of the problem the worst possible way and will come up with a rationale that escapes our imagination as to how we're engineering this scenario to hurt her.

Now that we know we're essentially stealing her power, what obligation do we have to inform her? While we joked about buying a crypto mining rig to plug in to her circuit, we actually decreased the load on the circuit since discovering the issue. Not being able to turn off all the circuits in our house is not ideal and is a safety issue. Discovering this issue will, however, be beyond the scope of any home inspection. It won't come to light until and unless we bring it to light. We would like to inform her and compel her to have an electrician terminate the outlet from her circuit so that we can have an electrician add the outlet to our circuit (it won't overload the circuit as it's a dedicated circuit for the kitchen outlets, under cabinet lights and garbage disposal). We feel that, while not really covered by the party wall clause, her being responsible for disconnecting the offending outlet and us being responsible for connecting it properly would be sharing responsibility in the spirit of the clause and overall fair and reasonable, despite our mutual disdain for each other personally. We also have an incentive to just ignore the issue and sell because we already know we want to move. Not saying it's right and not what we'd ultimately prefer but the involvement of this neighbor has a high likelihood of causing us unforeseen headaches because of her temperment towards us and paranoia in general.

Are we obligated to report this? Is our preferred solution fair and reasonable? Obviously none of the respondents are our lawyers and what is offered here does not qualify as legal advice. Thanks.