Backstage With Booth

[RJNorton]

I just found what I was referring to above. It's from p. 141 of Tom's book. John Selecman, who was an assistant of James Maddox, approached James Ferguson on Monday, April 17th, and quietly told Ferguson that he was in the alley Friday night when JWB rode up. He overheard Booth call for Spangler, and Booth told Spangler, "Now, Ned, you will give me all the assistance you can." Spangler responded, "Yes, I will, you can depend on that."

If Selecman were telling the truth did this mean Spangler was agreeing to either holding Booth's horse himself or making sure someone else would hold it? Or could this be interpreted as Spangler indicating to Booth that he (Booth) could depend on "backstage help?"