Script issue

Hi, I have a web which is currently hosted by Vodien SG. I have a big problem. I hope you can solve for me.
My current web with customized delivery system is unable to work. Reason : 1) Our web developer that developed the system had since called it a day and shifted back to Indonesia. Our web was written in PHP script that could support Linux.
However at that time the person that managed the hosting for us was window thus he contacted my developer to have it some script changed so that it could support window. We could use the system happily. In May 2017.
In order to save some money we migrated the web to Vodien (In 2017 Vodien only had Linux platform unlike today, they have both window and Linux) The above informations were not made known to us and we were unaware that there are 2 platforms, window and Linux. Thus on the fateful day of migration , the whole system died together. Scores of emails and telephonic contacts were exchanged.
Unknown to all of us including Vodien that this is the real problem. Now Vodien is saying that a web developer could do some changes and that everything can be back to normal and we will be able to use our system for downloading, scanning etc. Can check if you are able to provide such service.
Thank you