Correct me if I am wrong, but the Russo-German reinsurance treaty was a secret unacknowledged arrangement, right? However, was it a complete secret or an “open secret” that Austria & other 3rd countries had some awareness of?
As long as it was 'active' : yes, it was kept secret. ...
Until Otto von Bismarck let it be made public in 1896. This was part of his campaign of a grundging, out-of-date-old-man against Wilhelm II.
For your question : it falls too short.
First : Please keep in mind, that it was in the first place kind of a stop-gap-measure of Otto von Bismarck after the Bulgarian Crisis of 1885/86 that lead the break-up of the League of Three Emperors. He was in desperate need of something to keep the Russians at his side and draw them away from France, that at this time already started to make ... 'overtures' to the russian nobility. And it wasn't very popular with the leading political class in Prussia/Germany at that time - the 'Junkers' as there was kind of a tariffs-war between them and Russia on grain-exports of the latter.
Second : Please keep also in mind the circumstances that lead to the non-proliferation of the Reinsurance treaty which were quite mixed.
-The then chancellor Leo von Caprivi was an opponent to german colonial expansion and friend of detention with Britain. Almost his first foreign policy actions was the - aleady prepared by Bismarck - signing of the Heligoland-Zanzibar Treaty, meant as a sign to Britain that Germany accepts Britains superiority in colonial questions.
-On the other hand - despite the non-proliferation - he ended the grain-tariff-war in favor of Russia. Big part of the general opposition to him by the 'Junkers' for the rest of his life. Beside the more social domestic policy he tried in union with the Kaiser at that time.
-As being unfond of war, contrary to the german military (Alfred von Waldersee), that favored preventive wars against Russia as well as France already at that time, he himself would have been happy to prolong it. But as he gave the Foreign ministry the lead, they ultimatly ... persuaded him and Wilhelm II, that 'leaning' to Britain' as well as pursue a "middle-europe" policy with 'guiding' A-H would be preferable.
So it was Leo von Caprivi
- with the Kaiser against the military keeping the treaty with Russia for military (anti-war) reasons
- with the Kaiser and the SPD against the 'conservatives' about social policy
- with the Kaiser (and the industry) against the Junkers in trade policy
- against the Kaiser and the industry for letting colonies
- against the Kaiser about 'fleet-policy' (already a feature, when he was Chief of the Navy)
and your choices :
none of these as they stand there
as each of them would need a very different set of PoD(s) in the first place as well as afterwards, not talking of further needed butterflys. (As I tried to indicate with my above comments.)