Electrical Set Up

We just picked up our new van from being built out. This is our second van and with it we have massive upgrades compared to our first. However, we were concerned about the electrical/batteries set up in the garage and asked for them to create a ventilated cover so we could utilize the garage space without risk of knocking into the electrical system. Unfortunately, the company didn’t seem to keen on doing this and created a small cover just for our two 300ah lithium batteries. Before, there was thin butcher block trim to keep the batteries in place, but we noticed that they took that out when installing the cover and when we got home we saw that the cover had not prevented the batteries from sliding. We are disappointed that they couldn’t do more to protect the electrical system and now disappointed that they didn’t reinstall anything to keep the batteries from sliding out. Does anyone have any ideas of what we could do? We’ve returned the van already twice for modifications/fixes and would rather not take it back to them a third time. We will if it’s necessary, but we were hoping to try and DIY something. We originally asked if it was normal and safe to house the batteries and inverter on the floor of the van like that, without being on some sort of platform and they said that’s how they do it and it’s fine.. we aren’t so sure, so thought we’d also ask you all.

I’ve attached a photo of the original set up (the photo with the butcher block trim around batteries), then a photo of the cover in place, a photo of when the batteries slid and knocked the cover out of place, and a photo of the cover completely snapped off.

Thanks in advance for any tips/ideas/feedback.