All perfect praise be to Allah, The Lord of the Worlds. I testify that there is none worthy of worship except Allah, and that Muhammad is His slave and Messenger.
According to the view of many scholars, it is forbidden to eat the meat of the frog.
Ibn Qudaamah said in Al-Mughni:
"'All that is hunted from the sea is permissible to eat, except for the frog.' 'And this is also the view of Ash-Shaafi’i.'" [End of quote]
He also said:
"As for the frog: 'The Prophet forbade killing it.' [An-Nasaa’i] This indicates that it is forbidden." [End of quote]
Based on that, the frog excrement is considered impure.
Mukhtasar Al-Kharaqi reads:
"Whatever comes out of a person or a beast whose meat is not permissible to eat, whether it is urine or otherwise, is impure."
For more benefit on the Hadeeth forbidding killing frogs, please refer to Fatwa 353896.
Allah Knows best.