I don't know why no one else has brought this up. Marinades are defined as savory, usually acidic liquid used to flavor foods, especially meats. The acids in marinades, usually wine or vinegar, react with the meat surface, causing the proteins to tighten up, keeping the marinade from penetrating any deeper than that outer layer. They don't tenderize meat, but flavor the outside.
Valid methods for achieving tender meat is cooking properly for the meat type, massaging, or pounding to break up the meat fibers, using a tenderizing tool as in meat mallet, meat tenderizer (has blades of tines that again break up meat fibers), meat cube device (wheel with protruding blades that alternate cuts, as in cube steak), Stewing, braising, slow roasting, pressure cooking, and for more tender cuts that require little tenderizing, cooking to the proper temperature.
There are a good many people on this site who can help you create, or select a brine, or cook your meat cut in a host of different methods. But don't rely on a marinade to tenderize your meat.
Seeeeeeya; Chief Longwind of the North