It was effectively a bad idea to submit the app from a differentl account. Now, the app is viewed as belonging to it.
Are you sure the spam is related to this former submission ?
If so, did you explain in the notes to reviewer, with a written and signed statement from the junior engineer confirming what you say here ?
If that's not enough, may be you should also have the letter certified by a legal officer.
Topic:
App Store Distribution & Marketing
SubTopic:
App Review