I've been able to resolve this issue. 

I was able to deactivate the bank feed using Solution 3 in the instructions here.  I edited my IIF to include only the HDR and QB ONLINE account for my discover card.

The import fails for QB ONLINE records when when using the Import IIF button.  You need to use the "Import it for me. I'll fix it later" option.

Once this was done the account no longer had the lightning bolt in the accounts list & I had the option to setup bank feeds for this account again.

When trying to setup the bank feed I was receiving an 88888 error.

To resolve this I "Reset Intuit ID Settings" from the help menu.

Once done I closed QBDT & re-opened it.  I then logged back into Intuit from the Company > My Company menu.  I was then able to connect my discover card bank feed & download transactions.

I hope this will help others with this issue.