5 BTC of what remains is being used to hire a new dev to fix the source and maintain the code.
Fix the source? do you still have the source, and what needs fixed?
I may be willing to fix it, compile and release it properly, and ensure it's safe and running, along with ensuring there was a working block explorer, but I would not be willing to maintain it long term, nor to be associated with the project. It would be a one off job to ensure everything works, and primarily to fund development of my own continued work on Bitmark.