One of the seven criteria is that the cure must be permanent. No official determination is made until the person cured has remained cured for a reasonable length of time, depending on the disease. If it is a disease known to occasionaly go into natural remission, the case is not even considered.
In the first place, the disease has to be one for which no cure is known or extremely difficult to cure. The fact that we know medically how to cure the disease readily would mean that perhaps, just perhaps, whatever it is that effects the cure when treatment is given could affected this particular case in some accidental, unnoticed way. Even though that is so unlikely to have happened (if the treatment was not given) that it would require credulity to think that it could happen, still, the fact that it is remotely thinkable means that any disease for which a ready cure is known cannot serve as a possible miracle case.
2. the disease must not be in a stage at which it is liable to disappear shortly by itself
3. either no medical treatment has been given or it must be certain that the medical treatment given has no reference to the cure--if someone is dying of pancreatic cancer, giving him painkillers that are not in any way known to have the slightest ability to cure the disease would not be a problem
4. the cure must be instantaneous (to reduce the variables of possible natural cures through diet or exercise or whatever, over time)
5. the cure must be complete--the classic case of a blind man with an atrophied optic nerve who went to Lourdes, bathed in the water, began to see but still had an atrophied optic nerve--that was not a complete cure though it surely is an inexplicability.
6. the cure must be permanent--as explained above.
7. the cure must not be preceded by any crisis of a sort which owuld make it possible the cure was wholly or partly natural
Obviously applying these criteria, depending on the circumstances, can involve some degree of judgment call and medical experts can disagree. That's why a panel is employed.
I am skeptical of this particular case. It is being hyped by some but it strikes me as a poor case to satisfy the seven criteria. I wish the credulous babblers, whether Catholic or mainstream media curiosity-seekers would shut up.
But to say that the Church manipulates the process and canonizes whomever she wishes is calumny against the Church.