Default gateway on nodes

I hope I have the right category.

I have made a few changes last week as suggested by an IT guy that knows a lot more than I do. And unchecking the DHCP block on the nodes. This caused all of my cameras to loose their lease. Well I finally got most of them back working now but the Axis cameras that I have will not function thru the Axis Companion website any more. One thing I noticed now is the default gateway on several of the nodes now say.

while others have another node shown there.

So main question is how many nodes need the DHCP checked? If I uncheck the block sometimes cameras jump to another node and the link does not work 
and what is controlling the default gateway? I seem to get internet when I plug in to a remote site but the cameras are not getting back now.

Thanks
Rick KB0VZP