I don't see Bangladesh avoiding a whitewash against West Indies primarily because their batsmen are crap when compared to the Windies batsmen. They chased down a target like 230+ within 37 overs which itself says a lot.
Also, I don't see Bangladesh winning a T20 series against them either since we all know how destructive the Windies can be in that particular format.
I can't say anything before the toss. If Bangladesh wins the toss and decides to field, then there is a slight chance of Bangladesh winning the match. Batting is a bit easier in the second innings compared to the first innings and there is some movement of the ball in the first innings, which we don't see in the second innings. You can't say that Bangladesh bowlers can't move the ball. Bangladesh's bowling line-up is stronger than West Indies. But Bangladesh's batters can't score the runs that are needed in the West Indies ground. Bangladesh's batters can't put pressure on West Indies' batters, so it becomes a bit difficult for Bangladesh's bowlers to dominate the opposition. To beat West Indies in the West Indies ground, you have to score 320+ runs, then maybe West Indies' batters will give wickets under pressure and the match will be easy for Bangladesh's bowlers. If Bangladesh gets a chance to bowl early today, maybe we will see the aggression of Bangladesh's bowlers and the result of the match will be somewhat in Bangladesh's favor.
In today's match, we may see some changes from both the teams. In Bangladesh, we will see Taskin in place of Nahid Rana and Nasum Ahmed in place of leg-spinner Rishad. I don't see anything surprising if Hasan Mahmud and Parvez Hossain Emon are seen in the XI.
However, there will be no need for any changes in the XI of West Indies. Because every one of their players is performing well. Maybe they can rest one or two players. Maybe they can rest Alzarri Joseph and give Jediah Blades a chance to play the match. Since they have secured the series win with 1 match in hand, the change in their XI will be a bit unexpected or they can enter the field with an unchanged XI.