Bangladesh needs immediate panacea to prevent Test batting collapse

Longer and shorter formats of Bangladesh cricket going through reverse direction. Tigers are the fourth in terms of winning percentage in ODI with 65% wins from 17 appearances in 2018, after India (75%), England (74%) and New Zealand (70%).
But the contrast in five-day cricket is truly wired. They succumbed in four Tests among five matches they played this year with lone draw against Sri Lanka at home in January-February.
The batting line-up of Bangladesh had been catching at straw throughout the year. They even couldn't exceed the two hundred runs total in one of the last eight innings. Bangladesh accumulated 110 and 123 runs against Sri Lanka in February followed by four innings of 43, 144, 149 and 168 against Windies in June-July. The latest inclusions are the 143 and 181 runs' innings against Zimbabwe in Sylhet.
Dearth of Shakib Al Hasan and Tamim Iqbal can be taken as a reason for Zimbabwe-shock, but is it not a lame excuse for a team that have been playing Test cricket for the last 18 years? How far a team can go with such a poor pipe-line or with that extent dependency on couple of athletes?
The most dependable middle orders in Bangladesh batting order are the stand-in skipper Mahmudullah Riyad and former captain Mushfiqur Rahim duo. The 'in-laws' jointly went out of forms during the much needed period of the team. Besides, Test specialist Mominul, who is pronounced as the Bradman of Bangladesh, is also futile for a long since.
Another rational issue is the unavailability of the specialist batting consultant for Test side. Bangladesh appointed almost a complete set of new coaching stuff led by English man Steve Rhodes. South African Neil McKenzie appointed as the batting trainer but he showed apathy to remain with Bangladesh Test side. Therefore, Tigers are playing Test matches without having any specialist bating adviser. Although, Bangladesh cricket authority are working to appoint a 'batting master' as soon as possible.
Bangladesh trapped in their cage. Tigers spinners proven blunt against Zimbabwe except Taijul Islam, who hauled 11 wickets in the Zimbabwean dominating Test. Both Mehidy Miraz and Nazmul Apu were ordinary with the ball at home. Zimbabwean spinners including part-timer Sean Williams, on the other hand, got both carry and turn. It's another mysterious failure of home side in the maiden Test in Sylhet.
Team selection and playing eleven setting-up is also raises gossips. Mushfiqur Rahim's batting at six is also created much criticism.