[Python] Altair choropleth map selection interval and bidirectional linking

I want to make a bidirectional plot where the selected values through brush in the scatter plot appear in a different opacity in the choropleth map, and the selected countries in the choropleth appear in a different color in the scatter plot. It appears that the geoshape does not accept brushing, so I tried to overlay a "hidden" dots map but it also does not work. Any help is greatly appreciated. Thank you!

selection = alt.selection_point(fields=['income_group'], bind='legend')
brush = alt.selection_interval()

# code the choropleth map
choro_map = alt.Chart(countries).mark_geoshape(stroke='black', strokeWidth=0.2).transform_lookup(
lookup="properties.name",
from_=alt.LookupData(
final_country,
key="country",
fields=[
"log_billionaires_100_million",
"number_billionaires",
"billionaires_per_100_million",
"income_group", "country"
])
).transform_filter(brush).encode(
color=alt.condition(
selection & (alt.datum.log_billionaires_100_million > 0),
alt.Color(
"log_billionaires_100_million:Q",
scale=alt.Scale(scheme="tealblues", domain=[0.9, 8]),
title=["Log Number of", "Billionaires", "Per 100 Million"],
legend=alt.Legend(offset=0)), alt.value("lightgray")),
opacity=alt.condition(
brush,
alt.value(1),
alt.value(0.3)
)).project("mercator").add_params(selection, brush)

dots_country = alt.Chart(final_country).mark_circle(opacity=0).encode(
longitude= 'longitude_country:Q',
latitude= 'latitude_country:Q',
size = alt.when(brush).then(alt.value(1)).otherwise(alt.value(5))
).properties(width = 500, height = 250).add_params(brush)

scatter_plot = alt.Chart(final_country).transform_filter("datum.income_group != null").mark_circle(size=50).encode(
alt.X("total_tax_rate_country:Q", title="Total Tax Rate (%)"),
alt.Y("tax_revenue_country_country:Q", title="Tax Revenue (%)"),
alt.Size("billionaires_per_100_million:Q", title="Billionaires per 100M"),
color = alt.condition(brush, alt.Color(
"income_group:N",
title="Income Group",
scale=alt.Scale(scheme="set2")), alt.value("lightgray")),
opacity=alt.when(selection).then(alt.value(1)).otherwise(alt.value(0.2)),
).add_params(selection, brush)

alt.vconcat((choro_map+dots_country), scatter_plot, center = True)

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