Secondly, why is the EU technically bankrupt? Or is this a theoretical organization?
Because its liabilities are greater than its assets, or put another way, it spends more than it receives and does so structurally.
http://bruegel.org/wp-content/uploads/2018/03/PB-2018_01_cor...
EU budget commitments exceed payments by about €10 billion a year, leading to an ever-rising volume of outstanding commitments, known as reste à liquider (RAL). RAL is expected to exceed €250 billion by 2020.
The EU is not a company, it's effectively a government, and so it simply doesn't allow itself to go bankrupt in a legal sense. It can violate contracts at will because it ultimately controls the courts. So when it doesn't have enough money to make payments it has committed to, it simply delays those payments. This results in an ever growing backlog of delayed payments that can't be made because the EU doesn't have sufficient funds.
Note that this behaviour is illegal under the treaties. The EU is not allowed to spend more than it receives. It does so anyway because it correctly believes the member states are too weak to enforce the rules. Also, the EU controls the ECB and ultimately the ECB is keeping many member states afloat via massive bond purchases. Whilst the EU Commission cannot legally just print money to fund its own operations, in practice that's what it's doing - the ECB prints money and uses them to buy the bonds of insolvent member states, which then turn around and hand some of that money back to the EU as part of its budget.