I completely agree with you because if Zimbabwe did not play at their own venue, if they played at the venue in Bangladesh, the match would have been in favor of Bangladesh. Moreover, no one could show patience on the part of Bangladesh, in the case where a team like Zimbabwe has more than four centuries in two matches, no batsman has seen a century in Bangladesh.
There is hardly any difference between the two. Bangladesh can win only when the matches are being staged at home. And Zimbabwe loses their matches irrespective of whether they are being played on.