Service Tag Not Found

I purchased a used R630 and when I type the service tag in on Dell Support, I get an error saying there were no matches.
When I ask the company I bought this from their response was:
"The configuration has been changed from the original so using the service tag to find drivers specific to your server would not work. 
Depending upon the source we obtained the server from, it may be imported from Canada or another country which won't show up on the U.S. site. I know Dell also removes service tags from their system for returned demo units or if Dell has a vendor sell a large lot of equipment to resellers like us. "

1) Should this concern me?

2) Should I return this system?

Thanks,

Kevin