@VBalazs Good day!
it does not seems to be domino server version issue 
from logs it seems to be it is missing reference job details while create index for Tlog job
i request you to create a support case so that we can further check suggest next steps
 

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Machine : OST0VWLN02
File    : ln6dbBackup.log
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6012  2bb8  09/09 12:49:31 800723 1SendDirChange::wait]: failure during createIndex startup
6012  2bb8  09/09 12:49:31 800723 :::startCreateIndex]: ERROR!!!createIndex failed

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Machine : OST0VWMA02
File    : CreateIndex.log
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2016  247c  09/09 12:49:30 800723 INDEXCACHEDIR: getAfileIdByTime: no afile found for commCell 2 app 495 time 2147483647 type (requested) 2 copyId 0 refCopy 0
2016  247c  09/09 12:49:30 800723 INDEXCACHEDIR: update(): previous backup not found: errno=-2
2016  247c  09/09 12:49:30 800723 TCreateIndex::initialize index checkpointing remains disabled based on task options
2016  247c  09/09 12:49:30 800723 TCreateIndex::initialize Effective failover flags are: UseICS=FALSE, UseTL=FALSE, Checkpointing=FALSE (scheduler flags=LTRUE, FALSE, FALSE])
2016  247c  09/09 12:49:30 800723 TCreateIndex::initialize modifyDelimiter(\): control file case sensitivity setting could not be determined
2016  247c  09/09 12:49:30 800723 TCreateIndex::initialize ctrlFile rewrite failed
2016  247c  09/09 12:49:30 800723 TCreateIndex::initialize handleHardFailure: not initialized!
2016  247c  09/09 12:49:31 800723 TCreateIndex::initialize unable to access index cache directory
2016  247c  09/09 12:49:31 800723 TCreateIndex::initialize MSG: Cannot access cache directory for nOST0VWLN02\Notes Database\ServerLN1D:\Lotus\Domino\defaultBackupSet\transaction logs] in BCreateIndex].

@Sujay kumar Hi!
Thanks for your answer. Meanwhile, support case opened and they are working on the solution.
I’ll write a short summary after the solution.

Hi!

A not published additional setting was needed on Domino tran log subclient, but I not allowed to publish it. If you met with the same issue, open a support case and request for a new baseline in tran log backups.

Had exactly the same issue. If the steps would have been here, so I would have save time to resolve it, so there you go (went with 2nd option straight away):

-- Please try reinstalling the commvault agent and check the issue.

--  With the registry key in place, please initiate a FULL job for the default subclient.  Then, run an incremental backup for the Transaction Log subclient (with the key in place, it will convert to FULL).  Please let us know the results of both jobs.

HKLM\SOFTWARE\CommVault Systems\Galaxy\Instance001\LotusNotesDBAgent
Name: dwForceFullOnTrLogs
Type: DWORD
Value: 1

Please disable this key after the job is completed.