I changed 電話口 to 電話 because I thought a more correct translation of the Japanese with 電話口 would be "Please call him to the telephone." Without the 口, I believe it truly means "Please ring him up."

You are correct about the poor translation, but 電話に呼び出す is not a very idiomatic way of saying it.

You should only adopt sentences in your native language, jeffr. 🙂

Both points well taken. By way of explanation, I can offer the following.
1. I consulted with a native Japanese speaker beforehand who confirmed that the original sentence did not mean the same as the sentences it was linked to.
2. I would have just commented on the sentence, but the last time I commented on an orphaned sentence, I was advised to adopt it.

Nevertheless, my only interest is to get things as correct as possible. What do you suggest I do at this point?

I think the best thing is to restore the 電話口 and add a new English sentence "Please call him to the telephone." linked to it. You can then unlink 38458 from 201251. The German and Esperanto sentences are only linked to the original English one.
FWIW I monitor changes to the Japanese-English sentence pairs, which is why I noticed this one.

Thanks for the input. As you suggested, I unmodified the current sentence (and unadopted it) and I've created sentence #8177221 with the English you suggested. However, I am not able to do the linking/unlinking as I am not an advanced contributor. Perhaps someone else can do that?

I've linked the new sentence and unlinked the other. It's gone off with the German, etc. versions attached. Dunno about the indirect Russian sentences.