Not enough info : How shall/should the "2nd Revolution" conducted by Röhm and the SA take place ?
Esp. : What happens to Hitler ?
Pls don't forget, Hitler WAS - even after 3 1/2 years of Röhms reign - for the overwhelming majority of the SA-members, especially the "active" ones, the ONE AND ONLY DEMI-GOD. Without his "closeness" to Hitler, Ernst Röhm had almost nothing, beside his innermost circle of confidents/intimates (in several senses ...).
He would have to :
- bring Hitler on his side or
- put Hitler out of commission at all (aka kill him).
First I don't see to going to happen. Hitler was at this point already too "well" and deeply engaged with the "establishment" (that followed willingly his own need and deeds) and : Röhm was already too powerfull to be acceptable for Hitler to have him on his side.
The second ... could work, as a "revenge-crusade" for whoever got blamed for the killing of Hitler - at least for getting as much "support" as possible by the SA and at least partially the PO(
Party
Organization) as well. Though I doubt, it would be "enough" to topple the Reichswehr and the "regular" goverment.
The 4 1/2 million men Röhm shall be able to muster ...
More than half of the nominal SA-menbers weren't "active" SA, but "SA II", the "older" and/or inactive, "supporting" members, not "fit" enough for duty (aka hooliganism"). And even of the "active" "SA I" many were only "part-timers", when needed for certain activities (propaganda) and far from anyweher near a "fighting" fitness as well.
Then ... even that Röhm in the 20ies controlled a damn awfull lot of the illegal weaponry of the Reichswehr, this wasn't the case anymore in the 30ies, though the SA definitly had its secret weapons-depot. ... But nowwhere near to arm, what weaponsbearing-capable men he would have been able to muster.
I thinks its more realistical, that even in a (for Röhm) best case scenario he woudn't be able to muster more than 200k to 500k men, with a questionable military training at best, spread over the entire empire, of which imo not more than 100k to 200k would be armed at least with light infantry weaponry, but only very, very few heavy infantry weapons (MGs, a few minethrower perhaps).
So ...
without Hitler going with Röhm and staying chancellor : Röhm and the SA are toast - by the Reichswehr as well as SS as well as still some hiding commies (maybe).
with Hitler dead ... it will take only longer. There will be also some struggle within the PO, which wouldn't like to follow Röhm at all - esp. not with all the "new" posts they got within the goverment. In that case the Reichswehr might probably wait a few days, until the PO has realized, that their best bet is going with the goverment instaed the "Röhm-crusaders" - and smash the SA then, which still wouldn't - IMO - stand a chance against the Reichswehr by its inherent structural weakness (training, weapons, trained leaders).
However, when gunsmoke settles, you would see almost the same, as OTL, only later, with more power to the military, with some even more strikt "emergency laws" for some longer time.
Again, a lot would depend on Hitler fate. Without him we might see a reemergence of Gregor Strasser ? Or an outright military dictatoship under emergency laws by Schleicher ?