PESA and Micro-TESE

My partner has potentially obstructive and non obstructive azoospermia due to cancer and one testicle removal and a mesh hernia operation that has caused a blockage (yeah I know what are the chances 😞😫) we are now looking into surgery but first having his AMH checked which indicates how effective the testicle working; has anyone else had any experience/success stories similar to this or any advice/information they can give me!? TIA X