There's a fix posted here: https://www.reddit.com/r/Crostini/comments/98iudh/version_70035110_official_build_canary_64bit/

This regressed with https://crrev.com/c/1166926

I guess a symlink from /usr/bin/sommelier.elf to /opt/google/cros-containers/bin/sommelier.elf would work.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromiumos/containers/cros-container-guest-tools/+/7e82af1812c402c1d259f5141f0f28c85c44589f

commit 7e82af1812c402c1d259f5141f0f28c85c44589f
Author: Stephen Barber <smbarber@chromium.org>
Date: Tue Aug 21 18:21:21 2018

cros-sommelier: add symlink to sommelier.elf

BUG= chromium:876126 
TEST=gnome-mahjongg

Change-Id: Ifc19cead2b831a1c489f10285a768355509305a1
Reviewed-on: https://chromium-review.googlesource.com/1183943
Reviewed-by: Stephen Barber <smbarber@chromium.org>
Commit-Queue: Stephen Barber <smbarber@chromium.org>
Tested-by: Stephen Barber <smbarber@chromium.org>

[modify] https://crrev.com/7e82af1812c402c1d259f5141f0f28c85c44589f/cros-sommelier/BUILD

Fix pushed with cros-sommelier 0.15 deb.

 Issue 876907  has been merged into this issue.

App issue mentioned in   Issue 876907  is once observed on bob device on 10895.40.0, 69.0.3497.73. 
Reboot fixes the issue.

Feedback report: 85629915765

It looks like Chrome crashed in #6, and it's expected right now that GUI apps will fail to start in that situation. A crostini restart should fix that.

This issue still seen in 11021.4.0/70.0.3538.0 on setzer.
Feedback report: 85640192120

Verified on 11021.5.0, 70.0.3538.7 by opening linux apps.