This may be late, however, you can send items FBM without tracking information.
I would warn you that if you would like to scale up the business on the account and want it to last long, upload the tracking information. The tracking information has a direct impact on account health. Although very little, it still has an impact.
Its hard to do over $10k per month in sales without uploading tracking numbers for any orders, let alone $100k.
FBM without tracking number 
