PAA,
I am maskim that the loshon of Tosafos, especially in Moed Katan, is ambiguous and certainly not more in favor of my pshat. It is the content of Tosafos’s question that I think is better according to my pshat.
In regards to your second paragraph, you have not answered my question. My question is that the answer in the Gemara in Moed Katan doesn’t require an ukimta but according to you the Gemara in Sotah does require an ukimta. It would seem therefore that the answer in Moed Katan is better and Tosafos should ask his question in reverse.
According to me, while similar the two answers are different and the one in Moed Katan is significantly bigger chiddush and therefore Tosafos can reasonably ask that the Gemara in Moed Katan should say a smaller chiddush. Why is Sotah a smaller chiddush? Because from Sotah all you see is that you can change your mazal to your own gain or detriment, but you don’t see that you can change someone else’s mazal even if they don’t deserve it. In Moed Katan the Gemara is saying that through tefillah a person can change someone else’s mazal even if the other person doesn’t deserve it!!
On Reish Lakish, the mashmaos of the Gemara is that Reish Lakish statement was his introduction to the learning of Sotah, implying that a person would only have a wife who was a Sotah if he was a rasha himself. It would be a very odd introduction to Sotah if it only applied in a minority of marriages. I think the answer according to you, requiring a second marriage ukimta to Reish Lakish is very dochek and sort of defeats the purpose of what Reish Lakish was saying.
P.S. Thank you for brightening up my workday with a little learning!