Although we dont know what happened to his body , we are almost sure that his death this time was in absolute certainty .
First , only a sharingan can cast the izanami [ taken from naruto wikia ] ;
Izanagi can be used only by those with the genetic traits of the Sage of Six
Paths. The Uchiha, descended from the Sage, are able to perform Izanagi with
their Sharingan. Even with such an eye acting as a medium, gaining the power
to temporarily control reality's flow as the user sees fit comes at a price;
one has very limited reserves of time within a single eye for invoking this
technique. This technique would normally be used for only the most dire of
situations and for but a brief moment as after the Sharingan with which
Izanagi was casted exceeds its limit, the said eye becomes powerless and is
rendered blind permanently, with the rare exception that its sight and power
can be restored to the said eye by further evolving it into a Rinnegan.
Madara could switch between both the sharingan and the rinnegan effortlessly . but there is one thing we know for certain and that is when a tailed beast extraction occurs the jinchuriki faces certain death . when we saw that kaguya had burst out from madara we saw something similar happen , and the beast was extracted from him into kaguya and wasn't spit out until later when kaguya was about to be defeated . Madara was ultimately out of chakra and he couldnt even switch between the eyes at the end as we could see . If he didnt have the Tailed beast extracted maybe he could've.
There is another argument i have , after madara became the sage of six path's i think madara could no longer access the dojutsu powers of his sharingan . But this is only mere speculation.