Could the log backups happening simultaneously during the full backup
cause this situation?
No, simultaneous full and log backups have been possible since
SQL Server 2005, as Paul Randal states here in a post on concurrent log / full backups.
Here’s a question that came in – what changed in SQL Server 2005 that
allows concurrent log and full backups?
In SQL Server 2005, the restriction was lifted, but there’s a subtle
twist. You can do concurrent log backups with fulls BUT the log is not
cleared when the log backup ends. The clearing of the inactive portion
of the log is delayed until the full backup completes. This could
cause you to have disk space problems if your log generation rate is
huge and you’re relying on very frequent backups to manage the log
Also stated here regarding the many myths regardings backups.
I used a tool that puts them in order, so that's not my issue
If it is not the tool's wrong doing as you mention then I would try to look if there are any other log backups being taken in your backup history dmv's in the
Double check the restore procedure as well so that you are certain that you have all the log files (for example different paths after failing over the Always On Availability Group if the database is participating in an Availability Group, however Ola's procedure should take care of that).