If the GM wishes to figure out some ruling for this -- e.g., lowering the target number, requiring a minimum check digit, or both -- then it's certainly a reasonable addition. However, such additional combat rules, like the Grappling rules you'll never see, fall victim to two rules: KINS (Keep In Nomine Simple) and INING (In Nomine Is Not GURPS).
So you'll very probably only see those as optional house rules (which everyone can make suggestions for, if they want!), unless you switch to
GURPS In Nomine. Even GURPS In Nomine doesn't allow targeting a specific Force, as I recall, though; it's treated like an Aging roll.