I would also be very off put by that review…If only the reviewer had given more detail about the situation, maybe there was a different reason for the poor baby’s sudden passing. It is entirely probable that a commercially produced product could contain chemicals that are toxic to animals. These hutches are designed for outdoor conditions so they could contain waterproof sealants, paints, and other chemical concoctions used to treat the wood. In this situation, the first thing that comes to my mind is that maybe they use a lead paint and if the bunny chews the wood and ingests the paint that would be poisonous. I know that lead is not allowed in household paint, but I think it can still be added to exterior paints, so that is a possibility. Unfortunately, you won’t be able to know all of the chemicals that are contained in the product, but I think maybe looking for an indoor hutch would be better because maybe it would not be as heavily treated with chemicals. Some people build bunny condos out of NIC grids, but you would have to cover the wire flooring to prevent injury/discomfort. You could also look into DIY hutches, there are lots of good ideas out there using repurposed furniture. Good luck on finding something!

It says it is cypress fir, which I don’t think is suitable. Perhaps someone else can weigh in on that?

From what I can tell, they use this wood as it is “naturally weather and insect resistant”. Those qualities may be due to it having a lot of resin still in the wood. Does it have a strong smell? It could be a problem if a rabbit where to chew it.

Since you already have a pen, what about getting another and making a habitat using them? I recall a member here using a pen and putting a upper level in it and a roof for the top.
Or you could just use a pen with higher sides for when he need to be shut away. Or do you have other pets that could get into the pen?