I suppose you mean high availability cluster (failover cluster), instead of high performance cluster. The previous reply is about high performance cluster. High availability cluster (failover cluster) is supported by LFFTS.
There is a KB about deploying failover cluster, see https://support.laserfiche.com/GetFileRepositoryEntry.aspx?id=2204&mode=download. This KB is 3 years ago, and distributed search engine was not supported at that time. So that, two machines are required in the KB. Each machine has LFFTS and Laserfiche Server installed.
Since LF 8.3, distributed search engine is supported. I haven't tested failover cluster with distributed search engine. However I suppose all the following four failover cluster configurations should work:
1. There are 2 machines, each machine has LFFTS and Laserfiche Server installed (as mentioned in the KB);
2. There are 3 machines, one for LFFTS, and the other two for Laserfiche Server cluster.
3. There are 3 machines, one for Laserfiche Server, and the other two for LFFTS cluster.
4. There are 4 machines, two for LFFTS cluster, and the other two for Laserfiche Server cluster.
So the answer is yes to both of your questions.