Need help with the meaning of this sentence [MC failed to catch a strange creature- half cat half bird like, then he said this]


MC is a detective in his school .He's trying to catch a strange creature ,that
the student in his school are gossiping about.The school Public Moral
Department is chasing this creature too like him , but they're like rivals
competing with each other.

He tried to catch it (?) on the stair but failed and felt down. (it seems that
he received infos about this creature from the student ,some say it's a dog
,some say it's a cat but he did not so sure about those theories- he also
overheard a member of Public Moral Department said "I heard that it's a
rabbit" -He thought that "It seems their infos about that creature are no
different like mines" )

俺は面食らって、その生物を捕まえるどころか、バランスを崩してその場に倒れてしまった。

MC「いつつ……！羽に気を取られた」

謎の生物は、そんな俺に構わず悠々と踊り場に着地する。

**MC : "どういうことだ？ここに来て、まさかの鳥説……！？" (>> this is the line which i don't
understand)**

Strange creature (cat/bird ??)「んなな～っ！」

​そうして、妙な鳴き声をあげるとソイツは廊下の向こうへと駆けていってしまった。

I can only guess he meant "Could it be the theory people (the student in his
school) said that you're a bird was true ... !?" but i'm not sure .Much thanks
if anyone can help me understand the correct meaning of what he said (there is
a "....!?" missing part so I don't know what was he trying to say here too)
[![Context about the strange
creature](https://i.stack.imgur.com/4kUbW.png)](https://i.stack.imgur.com/4kUbW.png)




This 説 is a type of recurring humorous expression used in frivolous or otaku-
ish speech in recent light novels and such. 説 is a grandiose word meaning
"(public/academic) theory", but people sometimes abuse this word to say
something as simple as "It could be that...".

For example, someone may say this in a light novel:

> 太郎君、実は女の子だった説!?

This is normally taken as a joke that simply means something like "Could it be
that Taro is a girl (hehe)?". Without 説, this might sound like a genuine
doubt. This of course does not mean some academic society is seriously
investigating Taro's sex.

In your case, the creature basically appears to be a cat, but the guy just
noticed it could fly. So he is saying "Now I'm starting to wonder if this is
actually a bird..." or sometimes along those lines.

This type of 説 usually comes at the end of a sentence, so I don't think
something is omitted.

**EDIT** : ここに来て is a set phrase meaning "after all this", "at this (late)
stage", etc. For example, "え、ここに来てそれを聞く?" = "What? You ask that NOW?"

