That's not true. The 1982 consent decree doesn't prevent the GOP from pursuing suspected vote fraud, it prohibits the GOP from doing doing a set of specific things in the name of "ballot security." Specifically, the GOP agreed to
(a) comply with all applicable state and federal laws protecting the rights of duly qualified citizens to vote for the candidate(s) of their choice;
(b) in the event that they produce or place any signs which are part of ballot security activities, cause such signs to disclose that they are authorized or sponsored by the party committees and any other committees participating with the party committees;
(c) refrain from giving any directions to or permitting their agents or employees to remove or deface any lawfully printed and placed campaign materials or signs;
(d) refrain from giving any directions to or permitting their employees to campaign within restricted polling areas or to interrogate prospective voters as to their qualifications to vote prior to their entry to a polling place;
(e) refrain from undertaking any ballot security activities in polling places or election districts where the racial or ethnic composition of such districts is a factor in the decision to conduct, or the actual conduct of, such activities there and where a purpose or significant effect of such activities is to deter qualified voters from voting; and the conduct of such activities disproportionately in or directed toward districts that have a substantial portion of racial or ethnic populations shall be considered relevant evidence of the existence of such a factor and purpose; and
(f) refrain from having private personnel deputized as law enforcement personnel in connection with ballot security activities.
Left leaning Federal Judges, would certainly use those provisions to interdict official Republican efforts to control the very abuses that have been reported in the last few Federal elections. They are virtually all in precincts where the ethnic composition was a significant factor.
There are certainly ways to attack what has been going on; but the timidity of the RNC is bolstered by the very language that you quote.