On CentOS Linux 7, Convert2RHEL is installing an older version of the shim-x64 package (specifically shim-x64-15-7.el7_8.x86_64) than the latest available  version in the rhel-7-server-rpms repo (specifically shim-x64-15-11.el7.x86_64). That is not the expected state. Convert2RHEL should always install the latest available RHEL packages. Unless there are conflicts and in this case there are none.

Reproducer:

• UEFI=1 SYSTEM=centos7 vagrant up
• yum update -y
• reboot
• convert2rhel --debug -y --no-rpm-va --serverurl "subscription.rhsm.stage.redhat.com" --username c2r_main --password c2r_pswd --pool 2c94d1aa8608736d0186139c40392d11
• rpm -q shim-x64
  shim-x64-15-7.el7_8.x86_64

Subsequent post-conversion `# yum update shim-x64` updated the shim package to the expected shim-x64-15-11.el7.x86_64 version just fine.

# yum update shim-x64 -y
...
Updating:
 shim-x64                 x86_64                 15-11.el7                   rhel-7-server-rpms                 691 k
Updating for dependencies:
 mokutil                  x86_64                 15-11.el7                   rhel-7-server-rpms                  43 k
...
Updated:
  shim-x64.x86_64 0:15-11.el7                                                                                         

Dependency Updated:
  mokutil.x86_64 0:15-11.el7 

Looking at the available shim packages in rhel-7-server-rpms (https://rhsm-pulp.corp.redhat.com/content/dist/rhel/server/7/7Server/x86_64/os/Packages/s/)

shim-x64-15-7.el7_8.x86_64.rpm	2020-07-29 18:44	689K	 
shim-x64-15-8.el7_8.x86_64.rpm	2020-08-01 09:07	689K	 
shim-x64-15-11.el7.x86_64.rpm	2020-09-17 14:07	691K	

This might be related to customer case https://access.redhat.com/support/cases/#/case/03412830 where the system was unbootable after the conversion. We don't have a log from the conversion there but the conclusion was that there was a problem with the shim package and installing the shim-x64.x86_64 0:15-11.el7 resolved the boot issue.