This is unfortunately not a supported function yet.

https://support.google.com/docs/answer/3093377

Tip: You can't use table references in =INDIRECT yet. Try IMPORTRANGE instead.

IMPORTRANGE shouldn't require an INDIRECT

Syntax

IMPORTRANGE(spreadsheet_url, range_string)

The value for spreadsheet_url must either be enclosed in quotation marks or be a reference to a cell containing the URL of a spreadsheet.

The value for range_string must either be enclosed in quotation marks or be a reference to a cell containing the appropriate text.