I feel that Japan does best ignoring Nazi Germany, too far away for aid or trade. Only advantage they got out of the Pact of Steel was to get Italy and lesser extent Germany from selling arms to the KMT, and be a threat to the USSR, that went away in 1939 with the M-R agreement
They could have left the PoS in 1940. After getting French Indochina, they don't need the Germans anymore.
M, the date and sequence of events in OTL is rather different than you indicate
Japan's first pact with Nazi Germany was signed in late 1936 by Japan and Germany
only and was very specifically against Soviet Russia as was seen by it's title "Anti-Commintern". (
Aside: other mainly Fascist states joined later)
The actual "Pact of Steel" was signed by Germany and Italy
only in May 1939.
Hitler did court the Japanese to sign but they refused for much the reasons you suggested.
The Molotov - Ribbentrop pact in August 39 certainly questioned the Anti Commintern terms
but in November 1939, Germany
and Japan signed the "Agreement for Cultural Cooperation between Japan and Germany", which restored the "reluctant alliance" between them
Of course the Nazi successes versus France in May - July 1940 allowed the Japanese to pressure the new Vichy government over French indochIna
The actual terms were agreed by Vichy (and implicitly Berlin) in August but before the "peaceful" occupation was implemented fighting broke out on the ground in late September 1940 without any formal orders or declaration of war. The IJA was not exactly well disciplined
This practical cooperation brought the Japanese fully back to the Nazi table again.
This resulted in Japan
and Germany
and Italy signing the "Tripartite Pact" in late September,
in fact the very day after the fighting was stopped in FIC though whether that was significant I don't know
(
Aside: again a series of other Nazi sympathizer/puppet governments eventually signed this Pact somewhat blurring its name)
From the above it was seems that Imperial Japan thought it needed Nazi Germany distinctly more than you suggest
and that in the period before July 41 there was no window for Japan to cut these links
After that is another matter of course ...
BTW apologies for the multiple edits to tidy up my text. An old nerve condition has returned and is bollixing up my hand-eye coordination AGAIN 