Mh, can not tell you, don't know that.
But is "wajig new" not the same as "apt list --upgradable", after running "apt update"?
The only thing I have to mention is, that we are working with debian unstable!
I don't know how wajig can handle that.
Okay, apart from that, did you try the commands as root?
Ps.: What does the log files telling you, journalctl and so on!?