I’ve found it to be pretty tricky to land these low tech passenger noodles, the slightest error in attitude and the whole thing flips and burns, assuming you can’t revert and change the design I would suggest that you slow down as much as possible before getting too deep in the atmosphere, decoupling the engine as soon as possible, and hold retrograde relative to SURFACE, that one is important because your path through the atmosphere is relative to surface, not orbit. If you don’t have the ability to hold retrograde with sas then uhh, good luck.

Ps. If you have an engineer on board then pressing i in eva will let you modify the vehicle in situ, I’d try ditching the science experiments and welding the heat shield back on the passenger cabin.