I understand the desire to slow progression.
We don't have any reason to believe that this would, and considerable evidence that inserting hodgepodge concoctions into the bloodstream, if only because metabolizing such things would take more energy, even if they had no ill effects, would actually make things worse. There is also the matter of drug interactions, largely unknown for non-standardized pharmaceutical ingredients. There is no statement of quantities or concentrations -- right there, a huge red flag. Do you put pills in your body that way?
If you want your dad to consider known, standardized, quantifiable supplements that might help with energy and wellbeing, there are several threads here to that effect.