Credit to the following article: https://www.alhakam.org/location-of-qadian-in-appendix-to-khutbah-ilhamiyyah/
An allegation raised by the opponents is that Hadrat Mirza Ghulam Ahmad (as) has given the wrong location of Qadian in the appendix of Khutbah Ilhamiyyah, Ruhani Khazain, Volume 16, p. 22. Hadrat Mirza Ghulam Ahmad (as) writes that Qadian is located in District Gurdaspur of Punjab and is in the South West side of Lahore which is exactly East of Damascus (Khutbah Ilhamiyyah, Ruhani Khazain vol. 16, p. 22-23)
Firstly, this is not from the revealed portion of Khutbah Ilhamiyyah. Secondly, the new edition mentions that this was an error of the Katib and not Hadrat Ahmad (as).
This was a scribal error and the scribes missed “جس” before “سے” and wrote “قادیان جو لاہور سے”. Instead of writing “قادیان لاہور جس سے”, they clearly made a typographical error.
In Sitar-e-Qaisariyya, Hadrat Ahmad (as) writes:
“After this, the writer of this submission, Mirza Ghulam Ahmad of Qadian, who lives in a small village of the Punjab named Qadian; which is situated approximately seventy miles from Lahore in the north-east corner of the district of Gurdaspur. […]” (Sitara-e-Qaisariyyah [The Star of the Empress], Ruhani Khazain, Vol. 15, p. 111)
This shows it was a error of the katib and not Hadrat Ahmad (as). This is a weak allegation of the opponents.