Too close yes. What about something like
Edwina and
Thomasina (
Winnie, Win, or
Eda and
Tam).
Edwina and
ThomasinaLavinia and
ThomasinaVirginia and
ThomasinaGeorgianna and
ThomasinaYasmina and
ThomasinaEvangelina and
Thomasina
I don't mind that they rhyme so much as the entire last 3 syllables are virtually the same.