What we are talking about here are really two separate maneuvers, firstly a Windshear Escape Maneuver, during which the configuration should not be changed, and then once clear of the windshear transition into a go around with the resultant configuration changes.
A minor flap overspeed is really little cause for concern but trying to overthink the situation in the heat of the moment can lead you into trouble you don't need.
Regards,
BH.