I guess those numbers don't include the fact they have quite a few players on loan, yet to be paid off.
In Janaury 2017 Jovetic's loan will expire and they'll have to pay 14,5m euro if they want to keep him (conditional)
In August 2016 Telles' loan expires and they'll have to pay 8,5m euro to keep him (conditional)
In August 2016 Ljajic's loan expires and they'll have to pay 11m euro to keep him (conditional)
In January 2017 Brozovic's loan will expire and they'll have to pay 10m euro to keep him (conditional)
In June 2017 Miranda's loan expires and they have an obligation to sign him for 11m euro (obligation)
In January 2018 Eder's loan expires and Inter can negotiate a transfer with Sampdoria (conditional)
That's like 1/4 of their squad and lots of these players are among their best. They bet on these loans to bring them CL without investing much, kinda like we did when we were buying players back in 2010 and 2011.
They failed and now it looks bad.