Can't open .pbit - "File is encrypted or corrupted" message

Hi, having issues opening a pbit file. Running the latest powerbi (diagnostic info below). Other templates and reports work fine, just this one that I've not been able to open (I didn't author it). 

Read other posts here and none of the proporsed solutions (disabling preview features, unlocking file, clearing appdata folder, reinstalling) seems to make a difference. 

Template is a project in github.com

https://github.com/nbrown02/FlowViz2/releases/download/Release-1/FlowViz.Project.pbit

Already contacted owner of the above project as well.

Thanks

Feedback Type:
Frown (Error)

Timestamp:
2021-09-30T20:54:50.3699792Z

Local Time:
2021-09-30T16:54:50.3699792-04:00

Session ID:
5f6e8f84-5774-442a-a172-09e4c1e330ae

Release:
September 2021

Product Version:
2.97.921.0 (21.09) (x64)

OS Version:
Microsoft Windows NT 10.0.19042.0 (x64 en-US)

CLR Version:
4.7 or later [Release Number = 528372]

Peak Virtual Memory:
102 GB

Private Memory:
462 MB

Peak Working Set:
657 MB

IE Version:
11.789.19041.0

Model Default Mode:
Empty

Model Version:
PowerBI_V1

Enabled Preview Features:
PBI_JsonTableInference
PBI_ImportTextByExample
PBI_ExcelTableInference
PBI_enhancedTooltips
PBI_rdlNativeVisual
PBI_enableWebView2

Disabled Preview Features:
PBI_shapeMapVisualEnabled
PBI_SpanishLinguisticsEnabled
PBI_qnaLiveConnect
PBI_azureMapVisual
PBI_dataPointLassoSelect
PBI_compositeModelsOverAS
PBI_dynamicParameters

Disabled DirectQuery Options:
TreatHanaAsRelationalSource

Cloud:
GlobalCloud

DPI Scale:
200%

Supported Services:
Power BI

Formulas:

section Section1;