why select it?
just use ISketch.GetSketchPoints
Dim ExcelWorksheet as Excel.Worksheet
sketchPointArray = swSketch.GetSketchPoints2
For i = 0 To UBound(sketchPointArray) ' Get value returned by ISketchPoint::GetCoords
Set swSketchPoint = sketchPointArray(i)
KEEP IN MIND THE SKETCH POINTS COORDINATES ARE IN METERS
if your using millimeters than multiply by 1000 to get your match
Dim NewVals() as double = GetNewPoints
Loop through your excel file rows to match the sketch point values.
when found do this
swsketchpoint.x = newxFromyourExcelFile
swsketchpoint.y = newYFromyourExcelFile
swsketchpoint.z = newZFromyourExcelFile
to get stuff from excel
reference this topic
Function GetNewPoints(byval ExcelFile as excel.Worksheet) as double()
add the way to get them here
clear as mud?