Don't use soap. Use detergent. Laundry detergent. This should work well for a fabric suitcase without damaging it.

If there is leather that got soaked, use saddle soap on the leather part.

You don't say what type of liquor did the damage. Vodka? Gin? Brandy?

You say that it is "all hardened" so I am guessing that it is rather a liqueur and not a liquor. Liqueurs are loaded with sugar and would dry either hardened or sticky. Liquor is mostly alcohol and does not have the sugar in it and would have mostly evaporated.

Is the suitcase a nylon fabric or cotton duck? Spritzing the area with rubbing alcohol will help 'break down' the stain and then immediatly scrub it with the detergent.

If you know someone with a rug cleaner with an upolstery attachment try to borrow it. This is your best bet for saving your luggage.

Alcohol and sugar should come out easily but, liqueurs have herbal and fruit extracts steeped in them and this is what is going to cause a problem with staining, even after you wash the luggage. What is it that spilled? Blackbery brandy? Jaegermeister? Tia Maria? Knowing what the spill was can help with an answer on how to get out a deep dye stain.

Then there is the problem of getting the lingering smell out. If the spill was Ouzo or Rumplemintz the smell may not be intolerable. If it was Scotch or something, the luggage is going to stink and make your clothes smell bad. Store the luggage with charcoal and newspaper in it. (A good idea for storing luggage anyways.) And make sure the luggage is completely dry before storing it or it will mold.