I live in an old house with my parents (who are the homeowners), and have a problem where some of the electrical outlets in the oldest parts of the house have not been upgraded from two-prong to three-prong outlets. There are two outlets in particular that we have various electronics plugged into, one powering some networking gear and the other powering a TV and a desktop computer setup. In order to use modern electronics with these outlets, we use a combination of cheater plugs and extension cables, then run surge protectors off of those as needed. This setup has worked for years with no issues, but I remain concerned about its safety and efficacy over the long term. I have inquired with my parents to see whether they would be receptive to hiring an electrician to properly rewire those outlets, but they are of the "if it's not broke, don't fix it" mentality and do not wish to spend the money to update those outlets.
One idea that I had to help address this was to attach a wire to the ground tab on the cheater plugs and run that over to a grounded three-prong outlet on the same circuit to ground them. To do this, I would utilize one length of copper wire like so with closed-end wire terminals to connect the ground tabs from both cheater plugs together, then I would run a second length of wire from one of the cheater plugs to the nearest three-prong outlet and connect it using a ground adapter like this. All three plugs are located on the same circuit, with two of the plugs in the same physical room, so I do not believe there should be any major issue electrically doing this.
Would this be a viable solution for protecting these important circuits from ground faults? If not, is there a better solution that would provide a similar result? Remember, fixing the root cause of this issue is not possible at the present time, so an external solution is necessary.