q
.DisMax(c => c
    .Name("named_query")
    .Boost(1.1)
    .TieBreaker(1.11)
    .Queries(
        qq => qq.MatchAll(m => m.Name("query1")),
        qq => qq.MatchAll(m => m.Name("query2"))
    )
)

new DisMaxQuery()
{
    Name = "named_query",
    Boost = 1.1,
    TieBreaker = 1.11,
    Queries = new QueryContainer[] {
        new MatchAllQuery() { Name = "query1" },
        new MatchAllQuery() { Name = "query2" },
    }
}

{
  "dis_max": {
    "_name": "named_query",
    "boost": 1.1,
    "queries": [
      {
        "match_all": {
          "_name": "query1"
        }
      },
      {
        "match_all": {
          "_name": "query2"
        }
      }
    ],
    "tie_breaker": 1.11
  }
}

Action query = () => this.Client.Search<Project>(s => s
    .Query(q => q
        .DisMax(dm => dm
            .Queries(
                dmq => dmq.Term(t => t.Name, null)
            )
        )
    )
);
query.ShouldNotThrow();