Voltage hosts the infrastructure but have no access to the funds because your node is encrypted and only accessible to you via password. If voltage goes down then yes your funds would be inaccessible, but they cannot rob you.

Basically this is a good in-between when it comes to nodes - especially for digital nomads.

It should be noted that you can also point your voltage lightning address to an external self hosted node, but it can't currently be behind tor (which mine is).