The onion routing in Lightning is based on the Sphinx Mix Format described in this paper. The situation is different from Tor
We don't have entry and exit nodes in Lightning as all nodes are inside the Network.
In Tor a new connection along the path is as easy as creating a TCP socket between the tor routing nodes. In Lightning a payment channel with ...
To answer your question two things have to be known:
Routing fees are always charged from the recipient to the sender as the fee rate of later packages impacts earlier routing decisions.
Nodes get paid a routing fee to forward a package on an outgoing channel.
The first remark is not of importance for your case as the path only includes 1 routing node. ...