Hi Gina,
If I may chime in with what I currently understand of the history of this area. I welcome any criticism or input.
I think John is recognizing the fact that the Amekelites dwelt in the land of Canaan (Num 13:29) and shared many customs with the Canaan people due to them both inhabiting the promise land. Molek was the god that these people would sacrifice their children to by causing them to "pass through the fire." (2 Chron 28:3, Jer 19) The closeness of the Amekelites and the Canaanites is evident in the fact that they both joined together to attack Isreal after the Isrealites had departed from Egypt towards that promise land (Num 14:45). God had warned Isreal not to follow after the practices of the people who inhabited the land He was about to give them and to utterly destroy them so that they would not be polluted by their practices (Ex 23: 23, Ex 23:32-33, Numb 33:51-56, Lev 18:21).
Isreal's failure to destroy its enemies would lead them to follow after the pagan gods of the the land, including moloch.
Psalm 106:34-38
34 They did not destroy the nations, concerning whom the Lord commanded them:
35 But were mingled among the heathen, and learned their works.
36 And they served their idols: which were a snare unto them.
37 Yea, they sacrificed their sons and their daughters unto devils,
38 And shed innocent blood, even the blood of their sons and of their daughters, whom they sacrificed unto the idols of Canaan: and the land was polluted with blood.
Judges 2:12 And they forsook the Lord God of their fathers, which brought them out of the land of Egypt, and followed other gods, of the gods of the people that were round about them, and bowed themselves unto them, and provoked the Lord to anger.
I don't think its a stretch of the imagination by any means to believe that the Amekilites participated in the worship of moloch which included the sacrifice of "sons and daughters," and perhaps even infants.
You are right to point out that in that specific instance God did not mention their pagan practices as a reason for their destruction but God had long ago declared judgment on the people of Canaan for their wicked ways.
Genesis 13:12 Abram dwelled in the land of Canaan, and Lot dwelled in the cities of the plain, and pitched his tent toward Sodom.
Genesis 13:14 And the Lord said unto Abram, after that Lot was separated from him, Lift up now thine eyes, and look from the place where thou art northward, and southward, and eastward, and westward:
Genesis 13:15 For all the land which thou seest, to thee will I give it, and to thy seed for ever.
Genesis 15:13-21
13 And he said unto Abram, Know of a surety that thy seed shall be a stranger in a land that is not theirs, and shall serve them; and they shall afflict them four hundred years;
14 And also that nation, whom they shall serve, will I judge: and afterward shall they come out with great substance.
15 And thou shalt go to thy fathers in peace; thou shalt be buried in a good old age.
16 But in the fourth generation they shall come hither again [Land of Canaan]: for the iniquity of the Amorites is not yet full.
17 And it came to pass, that, when the sun went down, and it was dark, behold a smoking furnace, and a burning lamp that passed between those pieces.
18 In the same day the Lord made a covenant with Abram, saying, Unto thy seed have I given this land, from the river of Egypt unto the great river, the river Euphrates:
19 The Kenites, and the Kenizzites, and the Kadmonites,
20 And the Hittites, and the Perizzites, and the Rephaims,
21 And the Amorites, and the Canaanites, and the Girgashites, and the Jebusites.
Or...
Genesis 15:16 (TLB) After four generations they [Isrealites] will return here to this land [Canaan]; for the wickedness of the Amorite nations living here will not be ready for punishment until then.”
God bless,
Alex