Data/master node offline for extended period

I have a 3-node cluster that is used for monitoring. Each node runs the master and data roles. I just noticed that one of the nodes had been offline for a couple of months and after finding out why, the config had been re-written to default because another tech tried reinstalling elastic on that node. I got the config reconfigured for the node and able to start elastic on that node, but after starting the node, in the cluster when looking at metrics it shows no host, whereas when that host was shut down it showed 17 host. I also had issues logging in to kibana with that node on.

The node has about 63gig of data on the storage disk where the indexes are stored. Could this be due to the old node having old data. If I delete all the data from the node's storage would that allow me to bring that node back on and see my current data and act as a new node in the cluster? When I look in the elastic logs on that host, it does not show any errors when the elasticsearch service is started.

thanks

That should work, yes.