Which server-side sync I should go with?

Hi,

Here is what we currently have: CRM online, Exchange 2010 On-Premise & CRM for Outlook.

Challenge: Workflow emails will not go out some times due to user's operation error in Outlook.

Talking to CRM support, they've suggested we get one Office 365 E3 license so that we can use this mailbox as the dedicated account to send out workflow notification emails. In our Workflows, the sender is the dynamic value such as "created by". Is this the easiest solution to take this issue out users' hands without other potential issues?

Thanks

Calvin