Creating flowchart with DiagrammeR nodes and edges instead of graphviz - diagrammer

Question

I would like to create a flowchart using the DiagrammeR nodes and edges functionality with R instead of using the graphviz wrapper function.
However, I can't figure out how to make the edges straight to make it nice.
This is the graphviz solution that looks like what I want:
# Packages needed for the test
library(DiagrammeR)
# grViz solution
grViz("digraph flowchart {
# node definitions with substituted label text
node [fontname = Helvetica, shape = rectangle]
tab1 [label = '##1', group=gr1]
tab2 [label = '##2', group=gr2]
tab3 [label = '##3', group=gr3]
invis1 [style = invis, shape=point, width = 0, group=gr1]
invis1a [style = invis, shape=point, width = 0, group=gr2]
invis1b [style = invis, shape=point, width = 0, group=gr3]
# edge definitions with the node IDs
edge [arrowhead='none']
tab1 -> invis1;
invis1a -> invis1 -> invis1b; {rank=same invis1a invis1 invis1b}
edge [arrowhead='normal']
invis1a -> tab2;
invis1b -> tab3; {rank=same tab2 tab3}}
[1]: 'A'
[2]: 'B'
[3]: 'C'
")
This is my attempt to recreate the same graph with the nodes and edges solution:
# Packages needed for the test
library(DiagrammeR)
library(magrittr)
# Node and edge df solution
create_graph() %>%
add_node( # id 1
label = "A",
type = "group_1",
node_aes = node_aes(
style = "filled",
shape = "rectangle",
fixedsize = FALSE)
) %>%
add_node( # id 2
type = "group_1",
node_aes = node_aes(
style = "invisible",
height = 0,
width = 0)
) %>%
add_edge(
from = 1,
to = 2,
edge_aes = edge_aes(
arrowhead = "none")
) %>%
add_node( # id 3
type = "group_2",
node_aes = node_aes(
style = "invisible",
height = 0,
width = 0)
) %>%
add_edge(
from = 2,
to = 3,
edge_aes = edge_aes(
arrowhead = "none")
) %>%
add_node( # id 4
type = "group_3",
node_aes = node_aes(
style = "invisible",
height = 0,
width = 0)
) %>%
add_edge(
from = 2,
to = 4,
edge_aes = edge_aes(
arrowhead = "none")
) %>%
add_node( # id 5
label = "B",
type = "group_2",
node_aes = node_aes(
style = "filled",
shape = "rectangle",
fixedsize = FALSE)
) %>%
add_edge(
from = 3,
to = 5,
edge_aes = edge_aes(
arrowhead = "normal")
) %>%
add_node( # id 6
label = "C",
type = "group_3",
node_aes = node_aes(
style = "filled",
shape = "rectangle",
fixedsize = FALSE)
) %>%
add_edge(
from = 4,
to = 6,
edge_aes = edge_aes(
arrowhead = "normal")
) %>%
render_graph()