Kosher ground beef wouldn’t be likely to contain it. The trick is to find kosher ground beef outside of NYC in the U.S! It has to do with separating the beef from the sciatic nerve. In the US, it’s easier to simply sell the beef in the hindquarters to non-kosher processors.

I found an explanation here

koshereye.com

Because everything from snouts to tail can end up in “pink slime”, I would doubt that any Kosher certification organization would chance it.

In Israel, where they do separate out the sciatic nerve, because there’s little market for non-Kosher beef, there’s a chance they might use it.

The best way to get ground beef is to buy good beef and grind it yourself!