It’s Spring where you are and here’s a bit more for your step .
Forget the bus back to Viana and walking in , you’re too close to Najera.
LaGuardia is only a 20 minutes bus ride , go there.
If they drop you off at the bottom bus stop get the elevator to the city gates.
Now 4 S , do something that most of us want but are too regimented to try.
Get to Haro , enjoy this lovely , easy to walk city and then the following day walk to Najera or Santo Domingo.
There are people in the Camino fraternity who have done this when walking the Tunnel Camino from Irun , so it’s documented .
Alex will find it
If it’s attached to the Ebro I envy you.
Good luck seeing if this is possible and if there is a designated path go for it as the walk from Navarrette to Najera is like watching grass grow
I would ask in Haro & / or at your designated consignment.
We wish you all the best .