You are correcct, there is an SWD chip but no pins soldered onto the board. The schematics show the TC2030-IDC-NL unit. According to the Sodaq documentation the board can be debugged using the MCU Reset, SWCLK, SWDIO pins on this unit. However, without solderable connectors it will be difficult to connect to debug it.
I may acquire a Sodaq ONE instead, as this has sodlered SWD pins which can be connected via a Segger J-Link EDU module.