The issue described in this bug report is caused by wrong depencies for the package, in particular: clonezilla depends on drbl (>> 2.20.11-5), and right now a version of drbl in stable/testing/unstable is 2.20.11-7. But this version is too old, and it misses some important pieces which are needed for the current version of clonezilla to work correctly.
A proper solution for this problem requires update of drbl package to a newer version, compatible with the current clonezilla version. As a temporal workaround it is possible to install the latest version of the drbl package provided by the developers from here: http://free.nchc.org.tw/drbl-core/pool/drbl/stable/drbl/ For example, 2.30.5 works for me in buster. In particular, the exact problem described in the bug is caused by an undefined bash variable $msg_exit_browsing. It is used in ocs-functions script to build a dialog with a whiptail command which is then evaluated, and user's choice in the dialog (which is supposed to be a path) is then used as an argument to 'cd' command in the line shown in a screenshot from message #10. But $msg_exit_browsing is not defined and therefore it's evaluation results in nothing, but whiptail misses the expected argument and therefore instead of returning user's choice it prints out usage help (which is what we see in the screenshot). And using this output instead of the expected directory path causes the problem. In turn, values for all $msg_* variables are defined in files located in a /usr/share/drbl/lang/bash/ directory. But $msg_exit_browsing still still not present in drbl 2.20.11, therefore is the compatibility problem.
