Indeed, they just need to fly the devices, and parts for final assembly from the Medtronic factories in China.
In the current situation, it makes zero sense to spin new assembly lines when old ones are situated in the world's biggest manufacturing supercluster, and can be realistically scaled tenfold if they commit to that.
What I read going round Chinese BBSes now is that Medtronic's "factory" in Ireland is just doing a screwdriver assembly from Chinese parts, and all that just to do the infamous "Double Irish" manoeuvre