Rashi on Accepting Truth

The Rambam, in his introduction to his Peirush on Avos, Shemoneh Perakim, famously writes the following:

ודע, שהדברים אשר אומר בפרקים אלו ובמה שיבוא מן הפירוש, אינם עניינים שבדיתים מעצמי, ולא פירושים שחידשתים, אמנם הם עניינים מלוקטים מדברי החכמים במדרש ובתלמוד, וזולתם מחיבוריהם, ומדברי הפילוסופים גם הקדומים והחדשים; ומחיבורי הרבה בני אדם.
ושמע האמת ממי שאמרה.

My translation:

And know, that the words which I will say in these chapters, and in the explanation itself, are not ideas that I originated, nor are they my own novel insights, rather they are ideas that were compiled from the chachamim in the Midrash and the Talmud, as well as from their other writings, and also from the words of the early and later philosophers as well as from the works of many people. And accept the truth from the one who says it.

The Rambam goes on to explain that it is for this reason that he chose not to quote people by name in this work. He did not want the "inexperienced person" (thanks, S.) to disregard the statement because of its source.

In this post I would like to try to demonstrate that the Rambam's view in this matter is not the only view.

In Makos (5b) the gemarah relates the following incident:

ההיא איתתא דאתאי סהדי ואישתקור אייתי סהדי ואישתקור אזלה אייתי סהדי אחריני דלא אישתקור אמר ריש לקיש הוחזקה זו א"ל ר' אלעזר אם היא הוחזקה כל ישראל מי הוחזקו זימנין הוו יתבי קמיה דרבי יוחנן אתא כי האי מעשה לקמייהו אמר ריש לקיש הוחזקה זו א"ל רבי יוחנן אם הוחזקה זו כל ישראל מי הוחזקו הדר חזיה לרבי אלעזר בישות אמר ליה שמעת מילי מבר נפחא ולא אמרת לי משמיה

A woman once brought witnesses, and they were found to be lying. She then brought another pair of witnesses, who were also found to be lying . She then brought a third party. Said Resh Lakish: This woman has established herself [as someone whose purpose is to use false witnesses]. Said R. Elazar to him: Because she he established herself has all of Israel established themselves [to be suspected of testifying falsely]? Such a case happened also before the court of R. Yochanan, and Resh Lakish said "this woman has established herself". But R. Yochanan exclaimed: "Because she he established herself has all of Israel established themselves?" He (Resh Lakish) looked at R. Elazar rebukingly, saying: You have heard your statement from Bar Naf'ha (R. Yochanan), and you have not mentioned his name!

(Translation courtesy of Sacred-Text, edited by me to represent what the gemorah actually says)

What is not clear from this gemorah is why was Resh Lakish upset at R. Elazar? What exactly was his complaint?

There is a very similar gemorah in Kesuvos (25b). While the matter under discussion there is different, it does feature R. Elazar saying something to Resh Lakish which Resh Lakish subsequently heard from R. Yochanan. Again Resh Lakish was upset at R. Elazar and addressed the same rebuke to him. (You have heard your statement from Bar Naf'ha (R. Yochanan), and you have not mentioned his name!)

To this gemorah Rashi comments:

He [RL] turned his head around and stared at R. Elazar with an ayin ra'ah for he [RL] understood that R. Yochanan was the source for R. Elazar's words but when he [R. Elazar] said it [to RL] he didn't say it in the name of R. Yochanan, therefore he did not accept it from him.

Now in all honesty, I don't really understand Rashi's explanation of Resh Lakish's objection. But is there any other way to understand Rashi other than to conclude that Rashi (or perhaps, Resh Lakish) did not subscribe to the Rambam's dictum?