Agreed that is true, it's up to the donor to appoint more than one attorney, sensible also in case a sole attorney can't act thus voiding the power.
All attorneys would be informed leaving the route open for one of them to object.
It's no different to the rest of the system, unless there is an objection on prescribed grounds the OPG does not check anything about certificate providers and witnesses, to do so would be difficult because they may have changed address or died by the time application to register was made.
It's the same with wills, if there are sufficient people willing to collude it is possible to forge a will although if backdating it several years you would need a typewriter and maybe some old paper.
The system relies on the low chance of people colluding and the difficulty of one person forging the signatures.
Forcing solicitors to be involved in creating an LPA would be one way to overcome the problem but this is obviously not the way the COP/OPG are heading with the introduction of the on line tool.
Grounds for objection to registration are on P3 of
>>>THIS DOCUMENT<<<