Unable to bind to gridview in another usercontrol - wpf

Question

I have 3 user controls
One is the parent that holds a GridViewUserControl and a ExportUserControl
The GridViewUserControl and ExportUserControl have their own viewmodels.
When I click the ExportButton in the ExportUserControl I need to pass the gridview to a command in the ExportUserControl. Everything I try is always passing null.
How would I do something like this? ( This is giving the error "binding.elementname cannot be set while using binding.relativesource"
<telerik:RadButton Content="Export"
Command="{Binding ExportCommand}"
CommandParameter="{Binding RelativeSource={RelativeSource FindAncestor, AncestorType=view:GridViewUserControl}, ElementName=GridViewData}"
Margin="0,10,0,0" />
EDIT: Parent Control looks like this
<UserControl x:Class="Sample.Sample1.View.ParentUserControl"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:view="clr-namespace:GroundStation.Configuration.Viewer.View"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:telerik="http://schemas.telerik.com/2008/xaml/presentation"
mc:Ignorable="d"
d:DesignHeight="300" d:DesignWidth="300"
DataContext="{Binding Source={StaticResource Locator}, Path=Main}">
<Grid VerticalAlignment="Stretch" HorizontalAlignment="Stretch">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="Auto" MinWidth="150"/>
<ColumnDefinition Width="5" />
<ColumnDefinition Width="*" />
</Grid.ColumnDefinitions>
<Grid.RowDefinitions>
<RowDefinition Height="Auto" />
<RowDefinition Height="*" />
<RowDefinition Height="*" />
<RowDefinition Height="*" />
</Grid.RowDefinitions>
<view:ExportUserControl Margin="5"
Grid.Column="0"
Grid.Row="2"
Grid.RowSpan="2"
MinWidth="150"
/>
<GridSplitter Grid.Column="1"
Width="5"
Grid.Row="1"
Grid.RowSpan="3"
HorizontalAlignment="Stretch" />
<view:GridViewUserControl
Margin="5"
Grid.Column="2"
Grid.Row="1"
Grid.RowSpan="3"/>
</Grid>
</UserControl>