Okay so I went ahead and tried what was in the other one where I added trusted=yes because the archive that is linked in the first option doesn’t have a repository for Ubuntu 20.04. I added the Trusted=Yes to 3.6, 4.0 and 4.4 and I reran sudo apt-get update and this is what came from it.
Ign:1 http://repo.mongodb.org/apt/ubuntu trusty/mongodb-org/3.6 InRelease
Hit:2 http://us.archive.ubuntu.com/ubuntu focal InRelease
Get:4 http://us.archive.ubuntu.com/ubuntu focal-updates InRelease [114 kB]
Ign:5 https://repo.mongodb.org/apt/ubuntu bionic/mongodb-org/4.0 InRelease
Get:6 http://repo.mongodb.org/apt/ubuntu trusty/mongodb-org/3.6 Release [2,495 B]
Ign:7 https://repo.mongodb.org/apt/ubuntu focal/mongodb-org/4.4 InRelease
Ign:8 https://repo.mongodb.org/apt/ubuntu focal/mongodb-org/5.0 InRelease
Get:9 http://repo.mongodb.org/apt/ubuntu trusty/mongodb-org/3.6 Release.gpg [801 B]
Get:10 https://repo.mongodb.org/apt/ubuntu bionic/mongodb-org/4.0 Release [2,989 B]
Hit:3 https://dl.ui.com/unifi/debian stable InRelease
Hit:11 http://us.archive.ubuntu.com/ubuntu focal-backports InRelease
Hit:12 https://repo.mongodb.org/apt/ubuntu focal/mongodb-org/4.4 Release
Hit:13 http://us.archive.ubuntu.com/ubuntu focal-security InRelease
Hit:14 https://repo.mongodb.org/apt/ubuntu focal/mongodb-org/5.0 Release
Get:15 https://repo.mongodb.org/apt/ubuntu bionic/mongodb-org/4.0 Release.gpg [801 B]
Ign:9 http://repo.mongodb.org/apt/ubuntu trusty/mongodb-org/3.6 Release.gpg
Get:16 http://repo.mongodb.org/apt/ubuntu trusty/mongodb-org/3.6/multiverse amd64 Packages [15.4 kB]
Err:17 https://repo.mongodb.org/apt/ubuntu focal/mongodb-org/4.4 Release.gpg
The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 656408E390CFB1F5
Ign:15 https://repo.mongodb.org/apt/ubuntu bionic/mongodb-org/4.0 Release.gpg
Get:19 https://repo.mongodb.org/apt/ubuntu bionic/mongodb-org/4.0/multiverse amd64 Packages [18.4 kB]
Fetched 155 kB in 4s (35.2 kB/s)
Reading package lists... Done
W: GPG error: http://repo.mongodb.org/apt/ubuntu trusty/mongodb-org/3.6 Release: The following signatures were invalid: EXPKEYSIG 58712A2291FA4AD5 MongoDB 3.6 Release Signing Key <packaging@mongodb.com>
N: Skipping acquire of configured file 'multiverse/binary-arm64/Packages' as repository 'http://repo.mongodb.org/apt/ubuntu trusty/mongodb-org/3.6 InRelease' doesn't support architecture 'arm64'
W: An error occurred during the signature verification. The repository is not updated and the previous index files will be used. GPG error: https://repo.mongodb.org/apt/ubuntu focal/mongodb-org/4.4 Release: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 656408E390CFB1F5
W: GPG error: https://repo.mongodb.org/apt/ubuntu bionic/mongodb-org/4.0 Release: The following signatures were invalid: EXPKEYSIG 68818C72E52529D4 MongoDB 4.0 Release Signing Key <packaging@mongodb.com>
N: Skipping acquire of configured file 'multiverse/binary-arm64/Packages' as repository 'https://repo.mongodb.org/apt/ubuntu bionic/mongodb-org/4.0 InRelease' doesn't support architecture 'arm64'
W: Failed to fetch https://repo.mongodb.org/apt/ubuntu/dists/focal/mongodb-org/4.4/Release.gpg The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 656408E390CFB1F5
W: Some index files failed to download. They have been ignored, or old ones used instead.
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