The output you show (fatal error) suggests (to me) that openvpn is not available for the tablet, yet...I could be wrong, alternatively have a look here; https://openrepos.net/content/korppi/securefishnet

The developer is offering versions for tablet and from the write up, says it uses/downloads openvpn anyway, so I guess this is a Sailfishy UI for managing/using openvpn.

Regards,