Throttling In Exchange 2013

Have you run the throttling policy script which comes with EV?

based on what you describe it doesnt sound like EV is a factor if the messages arent even making it to the journal mailbox on the 2013 side. i found an old article that references the keys you tried but it's very old and doesnt reference 2013. if you are server/hardware bound on your new system, you might want to look into SMTP Journal Archiving with EV 11 (instead of the old method of sending all your email to a single mailbox in Exchange and then having an EV task pull them out.)

I did that's how I was able to get journaling to work at all on E2013.

Can you share the messages/error you get then relating to the storage queue?

We will eventually be upgrading to EV11 but for now we just need to get everything off E2010. The throttling IS on Exchange but I figured it couldn't hurt to see how others are getting around this. We do a high volume of mail/day around 3million split between four journal mailboxes.

in one of the old technotes i read about the keys you mention, it did say that you can increase them to 3 and 4 but again, that was for Exchange 2010. just spitballing here but it could be something else though like you might need more HT servers to handle the load or you might need to seperate the 4 journal mailboxes to multiple mailbox servers. you also might want to revisit the need for 4 seperate journal mailboxes. your EV servers are pretty beefy so maybe you can get away with 2 or 3. the fewer the better imho.

We have 39 HT servers in our environment and each of the mailboxes is running on their own server dedicated to journaling. The reason we have 4 journal mailboxes is because we have 4 standalone EV servers each processing a single mailbox. 

Here is the error:

Last Error: 432 4.3.2 STOREDRV.Deliver; recipient thread limit exceeded
Queue ID: \1121
Recipients:  journalingMailbox@domain.com;3;3;[{LRT=};{LED=432 4.3.2 STOREDRV.Deliver;

recipient thread limit exceeded};{FQDN=};{IP=}];0;CN=Evault_JournalDB5

39 HTs but are any of them dedicated to journaling? i'm sure you've already googled the crap out of your error message but i figured i'd post these articles just in case it helps provide some clues. 

http://enterpriseit.co/microsoft-exchange/2010/submission-queue-mailbox-database-thread-limit-exceeded/

http://www.networksteve.com/exchange/topic.php/Probling_with_Throttling_of_Emails_by_Exchange_2013_servers/?TopicId=44328&Posts=3

What is the size limit of messages in your environment? I have seen companies have an outrageous limit allowed above 20-30 GB causing issues

I would contact Microsoft, as it would appear that the issue isn't related to EV.