322 is definitely enough to win, no matter how batting friendly the pitch is. I know why I miss Bangladesh's previous bowlers almost every match. The four bowlers who have played regularly for Bangladesh earlier were expected to do well and surely bring victory to Bangladesh. 280 runs to 290 runs where the fans of Bangladesh would have dreamed of winning, Bangladesh cannot win by 320 plus runs against the West Indies as a visiting team, it must be a failure of the bowling unit. Since the Bangladesh team is considered to be a fairly strong team for the ODI format, I originally expected Bangladesh to do well in the ODI series, but that was not the case. Bangladesh was whitewashed in the ODI series.
Of course 322 runs was enough for Bangladesh to win, but still Bangladesh lost this match due to failure of their bowling unit. Of the four fast bowlers you mentioned in Bangladesh ie the four fast bowlers you mentioned missing, two were in the third ODI match, and the remaining two bowlers Mustafizur Rahman and Ibadat Hossain are not associated with Bangladesh in this series. When these four bowlers played for Bangladesh in a match against the opposition, they have consistently performed well then.
With T20 series ahead, there is no point in expecting too much because West Indies will definitely perform better than Bangladesh in T20.
Although West Indies are stronger than Bangladesh in T20 format, Bangladesh won today. Bangladesh have been whitewashed in the ODI series but there is no possibility of them being whitewashed in the T20 series.