I doubt re-entry was on the cards, this thing dragged its bum all over the atmosphere, mostly sub-orbital.
From the following link:
Ship 28 continued until second stage engine cutoff and entered into a coast phase in Space. SpaceX were able to complete the Payload door test and the cryogenic transfer test, however teams opted not to complete the in-space burn for Raptor. Ship 28 would then attempt reentry, however the ship would not survive.
However, with the loss of Ship 28 on reentry, SpaceX will need to perform a mishap investigation like the last flight. Overall, Flight 3 was a resounding success.
Ship 28 and Booster 10 excelled in nearly every aspect and nearly completed every objective…
www.nasaspaceflight.com
The fact that SpaceX has to do a mishap investigation implies that reentry was indeed on the cards and that something went wrong during a planned reentry, else if ship 28 was supposed to burn up on reentry that would not be a mishap and thus nothing to investigate.
And from another link:
SpaceX quality engineering manager Kate Tice noted on the stream that SpaceX wasn't intending to recover Starship anyway, and had been planning to crash it into the ocean.
On its third attempt, SpaceX launched its Starship and cruised into space, but lost the rocket after reentry to Earth.
www.cnet.com
So ship 28 was always intended to reenter and in essence crash land it in the ocean, presumably with all telematics operational until the very end … providing critical data as the the vehicles reentry performance
but it went boom (too early) and hence the mishap investigation
I believe the mishap investigation is an FAA requirement whenever some aspect doesn’t go to plan and the results can impact future launch licenses