He took her in with the assumption that she was a בתולה and it turned out that she was a בעולה; she receives a Monoh - כנסה בחזקת בתולה ונמצאת בעולה יש לה מנה
Summary:
The phrase שהרי כנסה ראשון (in the ברייתא) teaches us that she receives a מנה and so there is no purpose for him to claim, since in any event she will receive a מנה (for כנסה בחזקת בתולה ונמצאת בעולה יש לה מנה).
And let us be concerned that perhaps she
was מזנה while she was betrothed to him - וניחוש שמא תחתיו זינתה
Summary:
The question of וניחוש שמא תחתיו זינתה is that since רב אשי maintains נמצאת בעולה ולא כלום, we should allow the second husband a טענת בתולים (to pay nothing) in order not to dissuade him from coming to בי"ד to verify whether אשתו אסורה עליו.
Summary:
We cannot say there was only one תקנה of מאתיים, for today it is a מנה. We also cannot say that initially they gave her מאתיים without the reason of חזו דמזלזלי בהו.