I suspect that this coin was used as a solidus weight. A solidus usually weighs around 4.4- 4.5g. The filed down wolf and twins coin comes in at 4.3g, probably the lowest weight that a solidus would have been accepted.
OSTROGOTHS. Athalaric. Municipal Coinage. 526-534. Æ 20 Nummi – Half Follis (21mm, 4.31 g). Rome mint. [Helmeted and draped bust of Roma right] / She-wolf standing left, head right, suckling twins; above, Christogram between two stars; · X · X · in exergue. COI 84b; MIB 71c; MEC 1, 99.