Pink branch centers are not a sign of emerald ash borer, but you're right to be concerned, particularly if your tree is losing branches or generally looks unhealthy.  The usual signs of EAB activity are woodpecker activity around the tree and tunnels under the bark.  Attached is an excellent article on EAB in Minnesota; it includes information on warning signals of EAB activity.

https://extension.umn.edu/tree-and-shrub-insects/emerald-ash-borers