do you have 2 SMTPs configured? Is each account set to use the correct one?

Yes. I have two SMTPs setup correctly for each account. But for some reason copies of outgoing emails for Acct 1 were going into the Sent folder in Acct 2. The only way I could get copies of outgoing emails from Acct 1 put into the Sent folder of Acct 1 was to make it the Default SMTP. But I can't remove a Default SMTP. I'm trying to figure out what's going on and how to correctly align the SMTP without have to delete accounts and reset them.

So it is possible to know exactly what you have got and where, please post the following images.

As you have two accounts, make sure you post same image for both accounts. Tools > Account Settings select the mail account name so the Outgoing Server is shown bottom right. Post two images showing this - one for each mail account. See first image below.

then select 'Outgoing Server (SMTP) select the top default outgoing server post image. then select the other smtp server in list and post image. It should look similar to the second image below.

Each outgoing server will have a Username = email address. You must make sure that Mail Account A email address is the same as the one in the Outgoing Server which that Mail account is using to send. Please check that the Mail account name email address = the 'User Name' of the outgoing smtp which it is selected to use.