Drailyou'll be fine. it's not ideal, but I went years touring before getting a boot with a walk mode. Honestly it's one of those things. Without a walking mode, you don't know what you're missing. When you get a boot with walk mode, you'll never want to go back.
100% agree, i tour with the salomon xpro 120 which has no walk function, granted the longest trip i have done so far has only been a couple of days but with my ankle tightly in place with reduced movement within the boot it was fine.
The only thing that i would look out for is the formation of eventual hotspots on areas of your foot that move around more in the boot. For that just bring moleskin and band aids to cover up small blisters.