Seems communication was root of problem;[not Scam] No villains here
Brad not being available and OP intial Contact with Sweetwater being told parts were unavailable and only giving OP choice of Return or wait for parts;
Maybe should have given option of sending back and see if Sweetwater could first confirm problem and solve BEFORE return process. And ship back to customer no charge. which with hindsight could have been done.
But first contact was nothing wrong with Bass and you damaged it so it will cost you $600
Customer had made other purchases, didn't have reputation for multiple returns and may have kept Bass IF Screw problem was solved and could get Bass back if a few days.
As to communication I wanted to purchase a Mesa Subway 1x15 and emailed my 'Sales Engineer' of my intent to BUY Cab from him [but wanted to ask a couple questions and see if I could get a small discount.]
After another email and 3 days he finally contacted me explained he had been off and out of Store last 3 Days
My assumption is that emails to your Sales Engineer don't go to personal Phone or Computer or are not forwarded to him
PS: I bought Cab from him but was told Mesa is on the No Discount list and Computer wouldn't even let him if he wanted to
Reason I waited for him to contact me was being in Sales/management in past I didn't want him to have commision squabble if I placed order with another Salesperson