Such allegations can only be brought up by people who have no understanding of the Holy Qur’an.
Say, “O My servants who have committed excesses against their own souls! despair not of the mercy of Allah, surely Allah forgives all sins. Verily He is Most Forgiving, Merciful.(Chapter 39 verse 54)
The Holy Prophet(Saw) is commanded by Allah to call the believers “my servants”. There is nothing wrong with this and no one who has read the Qur’an should raise such an allegation.
In another ayah Allah states:
And whoso obeys Allah and this Messenger of His shall be among those on whom Allah has bestowed His blessings, namely, the Prophets, the Truthful, the Martyrs, and the Righteous. And excellent companions are these.(Chapter 4 verse 70)
Allah says we have to Obey Allah and Nabi(Saw) not Allah alone. To reach these stages which include prophethood, you need to obey Allah and his Prophet(saw).
Promised Messiah(As) himself said:
‘Say: O my servants who have committed excesses against your own selves despair not of the mercy of Allah, surely Allah will forgive all sins. [39:54] In this verse instead of: O servants of Allah; the Holy Prophet (sa) was commanded to say: O my servants. This verse was revealed in this form so that God Almighty might convey the good news of limitless mercies and might comfort those who are broken-hearted in consequence of their sins. Thus, Allah the Glorious desired to exhibit a sample of His mercies and to make it manifest to what extent He honours His faithful servant with special favours. By adopting the form: Say: O my servants; God in effect said: Look at My beloved Messenger and see at what high rank he has arrived through his perfect obedience to Me that now all that is Mine is his. He who desires salvation should become his servant. That is to say, he should obey him so perfectly as if he was his slave. Then whatever sins he might have committed will be forgiven him. The word ‘abd in Arabic idiom also means slave as it is said: ‘…a believing slave is better than an idolater…’ [2:222]
This all just shows the love Promised Messiah(As) had for the Holy Prophet(Saw). He defended him day and night while the anti Ahmadi “scholars” watched and had no answers to the allegations. He cried day and night till he received the answers to the allegations from Allah and would not leave seclusion till the answers came.