one thing you should clear in your mind this type of spinal surgery
primarily meant for relieving you severe pain
and secondarily for numbness and tingling.
so if your pain improve 50% after surgery it will improve with time.
and as your surgeon explain you that your problem was chronic numbness
and tingling part will take time to improve but how much and when it is difficult to say to any spine surgeon
so along with pain killer you can start pregabaline and gabapentine which will improve your neuralgic pain as well as tingling part.