HNN embedding theorem for countable groups not preserving amenability

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The well-known embedding theorem for countable groups by Higman-Neumann-Neumann says that

Theorem 1: Every countable group can be embedded in a 2-generated group.

One can prove this theorem using wreath product (instead of HNN-extensions) in order to preserve solvability, see Embedding Theorems for groups, Neumann-Neumann 1959

I know that with a similar but not identical construction one can obtain an analogous result for amenable countable groups:

Theorem 2: Every amenable countable group embeds in a 2-generated amenable group.

See HNN Embedding Theorem for Amenable Groups?

My question is the following: Is there a countable amenable group $G$ such that the Neumann-Neumann construction (theorem 1) fails to preserve amenability?