The first and only example, until recently, that I had seen of this variation turned up in 2015 on eBay. I can’t recall if I found it completed or was outbid but I have been trying to track down this variation since. Not on any of the dozens of want lists or master set checklists sent to me by E&V collectors, this elusive variation, so far, has only shown up on Todd Benzinger’s card. A few 1990 Donruss experts have claimed that other cards in the Grand Slammers set can be found with the red star on front too, however, I have yet to confirm this.
If you have photos of any other 1990 Grand Slammers with a red star on front, please send to: jacksoncoupage@yahoo.com and I will update this post with a credit.
Junk Wax Gems 
I have one of these in my office, but its locked due to Covid — will grab once I get in there