What did Senator Grassley know about Jan 6 and when did he know it?

[Joinfortmill]

https://www.dailykos.com/stories/2021/12/11/2068803/-So-why-did-Chuck-Grassley-expect-Pence-s-absence-from-the-Capitol-on-6-January

'Was Pence worried he’d get “disappeared” on Insurrection Day? The ambiguity comes from the multiple descriptions of holding Pence within the confines of the Capitol. It looks like Grassley was expected to be part of a scheme on 1/5 to substitute for Pence who perhaps the seditionists expected would be “detained” by the Oath Keepers. The Meadows Power Point was presented on the hill on 4 January and on 5 January Grassley was confused about Pence “not being there. The witness list for the Select Committee gets longer.'