Fixed matches

[cosmicsports]

Everybody receives emails and facebook alerts for fixed matches.
They are scammers of course.
Three years ago there was one of them who created an elaborate facebook profile with many supposed "friends" saying "thanks", "superb", "keep up the good work" and the like". Now this page in the mornings somehow disguised itself to a different page about holiday resorts, with pictures of nice beaches and many friends again who followed it. Then it was switching back to the football tips page.
In the end it all disappeared of course, but lately I see some pro looking websites doing the same more or less thing.

On two or three occasions I responded to them and I said "give me twenty of your tips in code and we break the code after the matches have been played".
If they accept then I can test them but without taking unfair advantage.
They never respond back to such a request. My indiscreet emailer vanishes !
Only on one occasion did one write back and he said "I 'm a member of the Russian mafia and I 'm coming to get youououuououou" !

But seriously I wonder what if one really does accept the challenge in the end.
How to actually make this into a fullproof test ?
I mean I can codify the phrase "the rain in Spain stays mainly in the plain" in infinite ways, send it to you and then after the designated date send you the key to decode it.
But what if I trick you ?
I read somewhere that the German enigma machine used in the war had a nasty backup feature that was causing problems to the allies.
The allies decrypted the message but it was proving to be a false message and to decrypt the correct message they needed another key, which eluded them.
So our fixed match tipster could do this:
He sends me a key that opens the message as "Arsenal - Newcastle home win" but if the home win did n't happen, he sends another one that opens it as "Bayer Leverkusen - Panderborn home win", which did happen.
Is there a way in code making to make this action impossible ?

 

[cosmicsports]

I think I can do this.
Suppose the message is "m".
With the encryption key "K" I generate the jumbled message "f(m)" and with the same operation I also generate the decryption key "L".
I mail the "f(m)" and when the time comes I also mail the "L".
"L" depends on "K" but also on the contents of the message "m".
But you, the recepient, know both "K" and the encryption method that creates the jumbled messages.
Now that you also know "m", you can by way of verification re-encode and you should recreate the same jumbled message "f(m)" and the same decryption key "L".
It looks to me that prevents foul play or does n't it ?

 

[cosmicsports]

 

[cosmicsports]

I did not express myself well in the previous posts.
When I said that both persons must share the encryption metod I meant an exe file that produces the cryptograms and also decrypts.
I did not mean to say that we have the formulas writen on a piece of paper !

There is more to it.
The receiver also must not be able to cheat and view the tips without paying.
To achieve this, the encryption-decryption system must be created by somebody who is above suspicion.
Who is above suspicion ?
There are the email reminder services of course (send email to the future). Those are ok but I noticed they don't print the date.
I searched my mails and found one such saying "remember to call Steve" - some Steve I had to call and mailed the reminder to myself using "send to the future". It says Nov. 1 2016 but this is the day I received it, it does n't say the date I mailed it.
So the only one above suspicion is really the sender himself ! He has to construct the system and share it with me.
In this way he cannot cheat -because of the specifications I gave previously- and also I cannot cheat.

This logic problem is never solved completely though.
The best way is if the reminder services make the emails better and include the date sent. But in theory they could be part of the cheating scheme themselves.
Also exe files maybe can be reverse engineered. I don't think so because I tried once after I lost a source code in a computer accident and could n't do it, yet maybe there exist labs who can do it.