Yep, it's a strut. Front band, if I remember. He should have snugged the front band before pulling the pump. Likely wiggling the pump out moved the band around enough to let the strut fall out. It's also possible that a thrust washer or two may have slipped out of position if the input shaft was allowed to move forward. If the pump is just put back in with the washers mislocated, things will grind themselves up. May be best to check before reassembly.