Great question — answering as the UphillTech team:
Most likely, what you need is not at all a hack. You need to contact some shop in your area specialized in dealing with leather, and ask them to support you. Why? Because whatever will attack that glue for removal probably has the ability to destroy the leather too - either totally or partially - which you want to avoid. And my typical joke: you always have the alternative of using fire, scissors, or covering the entire jacket in glue :)
Full answer by virolino: https://lifehacks.stackexchange.com/a/27845 (CC BY-SA 4.0).
Need it done for your business? UphillTech.