This means selling 18k licenses for years. Moreover, how many licenses should be sold for fulfill the €7M debt? 140k licenses. Considering to pay back this debt in 10 years without interest (at this time interest is not less than 5% per year and 1.05^10 = 1.63) it meas to sell 18k+14k=32k licenses per year for 10 years. Considering also the interests, then 18k+23k=41k licenses per year for 10 years. Europe has 764M habitants, it means that 0.05% of them will buy a license in the next 10 years. The 0.05% includes new born babies upto 99yo grannies.
This just to stay alive and supporting the current hardware which will be 15-20 years old in 2033. To develop further SFOS, we can assume that they need €2M per year (900k of loss plus 1.1M for further developments) which are 63k of licenses per years, sold to 0.08% of the entire Europe population in the next 10 years.
As you can see, there is something broken in this business model and Volla is not much different.