IMO

when a company goes bankrupt , it must announce insolvency

Deutsch term (edited): mit den Konditoreien Insolvenz anmelden

'declare insolvency' is the normal collocation (see sketchengine.co.uk). 'Confectionary' firstly should be spelled 'confectionery', but in any case, on its own, is old-fashioned when referring to a shop. Either 'confectioner's shop', 'confectionery shop' or simply 'cake shop' would do.

First of all "file for bankruptcy" is a US expression and it includes both personal bankruptcy and company liquidation.
We don't know from this text whether this business was a sole proprietor (who would, IN UK parlance, declare himself bankrupt) or a company (which would appoint a liquidator).
In addition, there are other permutations, such as IVAs, CVAs, informal arrangements, etc. etc.

If you want a "catch all" phrase for European English I would use "insolvent/insolvency" which embraces all of these.