It is not about subordinate lending but about better conditions on the bank loan in which KFW is considered subordinate and therefore irrelevant for the determination of the conditions.
In the end, however, everyone just cooks with water again.
I think the OP is already aware that the KFW loan does not represent "real" equity but only reduces the loan-to-value ratio.
Hypo Vereinsbank does this as well or at least did so when we requested financing two years ago. However, the conditions were overall significantly worse than with the bank where we ultimately signed.