You Wish! As time goes by and more healed your argument weakens...wait it never had any strength to weaken because it was always merely an opinion. Jesus Christ, is what stands between your argument having any weight, merit or truth.
You would have to disprove he was the Son of God and did what he did. Not luck of that any time soon. Which leaves you with less hope than Bob Hope and that is in fact No HOPE...
As I have mentioned previously what we might describe as 'spontaneous healing' is actually much more common than we might think - actually it happens all the time, for most trauma or illness. So the physiology of the body is well set up to achieve this. Sure there are cases where the body's physiology is overwhelmed by pathology or trauma to an extent where it cannot successfully heal itself and medical intervention is necessary - but in every case there will be a physiological response attempted and many medical treatments are designed to work alongside or augment the body's natural response.
Given that most pathologies and most physiologies are a spectrum it isn't surprising that you will get occasional circumstances where the pathology is at the low end of the spectrum and the physiological response at the high end of the spectrum and therefore spontaneous healing or remission will occur for conditions that usually don't heal.
So far so completely 'natural'.
Further it is the case that there are things that can boost (or suppress) our natural healing abilities - and those are often linked to our psychological state of well-being. So for example someone who is clinically depressed will often has a suppressed ability to fight off disease through suppression of their immune system and physiology. Conversely things which boost well being can enhance the immune system's ability to fight off disease. Just this week singing in a choir was reported to have this effect. I don't doubt that for believers praying or worship may have a similar effect to choral singing, but again this is entirely natural, through psychological effects and their link to the functioning of the immune system and other physiology.
But of course none of this requires a god, nor Jesus etc and of course there is absolutely no evidence whatsoever that spontaneous healing for conditions where spontaneous healing isn't the norm, is anything other than a rare but completely natural phenomenon.