Hi @T Crha
I did a test in my environment and the problem is the same as yours. Although we have add this guest in our Teams, the guest could not see our Teams organizations.
Then I checked the setting and found in this settings, it provides the features when you have Teams Exploratory license. So i could make sure Teams Exploratory license is not provide the guest access in Microsoft Teams. This maybe the reason why you could not see the Team in your client.
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