Can't run e2e tests with nethermind only

[abi87]

If I change tests setup in testing/e2e/config/config.go to have a nethermind only networks as follows:

func defaultValidators() NodeSet {
	return NodeSet{
		Type: "validator",
		Nodes: []Node{
			{
				ElType:   "nethermind",
				Replicas: 5,
				KZGImpl:  "crate-crypto/go-kzg-4844",
			},
			{
				ElType:   "geth",
				Replicas: 0,
				KZGImpl:  "crate-crypto/go-kzg-4844",
			},
			{
				ElType:   "reth",
				Replicas: 0,
				KZGImpl:  "crate-crypto/go-kzg-4844",
			},
			{
				ElType:   "erigon",
				Replicas: 0,
				KZGImpl:  "crate-crypto/go-kzg-4844",
			},
			{
				ElType:   "besu",
				Replicas: 0, // Besu causing flakey tests.
				KZGImpl:  "crate-crypto/go-kzg-4844",
			},
		},
	}
}

func defaultFullNodes() NodeSet {
	return NodeSet{
		Type: "full",
		Nodes: []Node{
			{
				ElType:   "nethermind",
				Replicas: 5,
				KZGImpl:  "crate-crypto/go-kzg-4844",
			},
			{
				ElType:   "reth",
				Replicas: 0,
				KZGImpl:  "crate-crypto/go-kzg-4844",
			},
			{
				ElType:   "geth",
				Replicas: 0,
				KZGImpl:  "crate-crypto/go-kzg-4844",
			},
			{
				ElType:   "erigon",
				Replicas: 0,
				KZGImpl:  "crate-crypto/go-kzg-4844",
			},
			{
				ElType:   "besu",
				Replicas: 0,
				KZGImpl:  "crate-crypto/go-kzg-4844",
			},
		},
	}
}

func defaultSeedNodes() NodeSet {
	return NodeSet{
		Type: "seed",
		Nodes: []Node{
			{
				ElType:   "nethermind",
				Replicas: 1,
				KZGImpl:  "crate-crypto/go-kzg-4844",
			},
		},
	}
}

no block is finalized. This does not happen with other clients (or combination of them)