Your foot is the identical size to mine (28.5) 11/11.5 street shoe
I bought deeluxe suzukas last season in 28mondo with the thermo fit liners.
The fitters at fanatyko blew the shell out just a touch on out side edge of foot just back of little toe and just a touch on out side edge of big toe on both boots.
After that we molded the liners.
I have perfect fit now that the boots/liners are broken in
I asked about sqeezing my foot into a 27 shell, they said it could be done but they didnt dislike me that much,(it would have been tiiiiiiight)
in summary go for the 28 shell if your foot measures 28.5, the boot shell may require a bit of pushing out laterally by a good fitter but it will be worth it in the long run,