Why are Muslims trying to look to non-Muslims for help in convincing people that Muhammad is a great guy? I find it strange, shouldn’t they want people to go to the source of Islam (i.e. Qur’an, Sunnah) to learn about the prophet of Islam? Here’s a black stone worshipper who appeals to the kufr to prove Islam.

Makes sense right, if you want to learn about science you read science books not direct someone to watch StarWars, or if you want to learn about cooking you wouldn’t learn from reading automotive magazines; or if someone wants to know about Jesus Christ you tell them to read the Bible not Tipitaka (Buddhist scriptures).
Let’s learn some facts about Muhammad.
It turns out that he was bewitched (under black magic) for 6 months to 1 full year.

Definition of Bewitch (bewitched; bewitching; bewitched)
merriam-webster.com
1 a: to influence or affect especially injuriously by witchcraft
b: to cast a spell over
If Muhammad had a black magic spell cast on him, it’s possible that he could have imagined an angel (Jibril) appearing to him in a cave and giving him Qur’an. It’s certainly not far-fetched as the Hadith says Muhammad was imagining things he did but in reality, he didn’t do what he imagined he had done. It was so bad that he thought he had sexual intercourse with his wives, but it’s narrated he really didn’t. That must have been one crazy trip for Muhammad, he couldn’t tell if he had sex or not!
Here’s the Hadith that says Muhammad thought he had slept with his wives but did not as the effects of the magic were wreaking havoc on his mind. Clearly, Muhammad is mentally ill, how would anyone think of following someone under the influence of black magic?

I certainly cannot take this man seriously, he suffered from hallucinations! How bad do you think the situation was that a man doesn’t know if he had sexual intercourse?! It’s not the same as leaving your house and you wonder if you left the light on or locked the door.
Muhammad couldn’t get his story straight with all the contradictions in the Qur’an, what god doesn’t know what he created first? If compare 2 verses the first in Surat al-baqarah and the other in Surat al-nāziʿāt we find that Allah is experiencing Alzheimer’s disease[1]

Take notice of the these important parts of verse 2:29.
It is He who created for you all of that which is on the earth. THEN He DIRECTED Himself to the heaven, … and made them seven heavens, …
In the following verses, the order is completely different!

Are you a more difficult creation or is the HEAVEN? Allah constructed it. He raised its ceiling and proportioned it. And He darkened its night and extracted its brightness. And AFTER that He SPREAD THE EARTH.
In verse 2:29 it says the earth was created and then the heavens, but in verses 79:27-30 the heavens were created first and then the earth; that’s a clear contradiction.
Allah didn’t know which one he created first heaven or earth, and this is supposed to be a book from god?!
Conclusion
It’s very interesting that a Muslim would appeal to a non-Muslim in order to bring a positive spin on Islam. We have non-Christians who say Christ was a “great teacher and man,” but we don’t have to appeal to unbelievers to make Christ look good. The Lord Jesus and the Bible stands alone above all other scriptures. May these Muslims who say such silly things have their eyes open to the truth of the Son of God Jesus Christ!
Footnotes
[1] Alzheimer’s disease is a progressive neurologic disorder that causes the brain to shrink (atrophy) and brain cells to die. Alzheimer’s disease is the most common cause of dementia — a continuous decline in thinking, behavioral and social skills that affects a person’s ability to function independently. Mayo Clinic (2022). Alzheimer’s disease. Retrieved from https://www.mayoclinic.org/diseases-conditions/alzheimers-disease/symptoms-causes/syc-20350447