Breaking in Salomon quest echo boots

Hi all,
I’ve planned a 6-day half Alta via 2 hike in the Dolomites in mid-August. Two weeks ago, I took my hiking boots (Merrell Deverta) to a cobbler who confirmed that the midsole is worn out. As a result, I bought a pair of Salomon Quest Echo boots which have a much stiffer sole and better traction for scree terrain and technical difficulty of AV2.
I tried them on a few short walks and did a 12km (almost flat) hike last week and started feeling pain in the balls of my feet and foot fatigue already at 10km or so. Now I’m totally panicking about returning these and looking for yet another pair of boots that I may not fully break in before the trip.
Do you have any recommendations for how I can address this? I have small (eu size 36) but relatively wide feet. My feet don’t particularly squished or compressed in the new Salomons. Any ideas for insoles or different lacing options that can help with the pain?
Thanks!