Has anyone done this before with CX (not the route, but the dropping of legs with connections across 2 tickets)?

I have a ticket in V class:

TPE-HKG-PER-HKG-TPE

and want to insert a I class

hkg-sin-hkg

but it's a LOT cheaper to buy

tpe-hkg-sin-hkg-tpe

My parameters: I'd need to do a quick connection when flying PER-HKG-SIN, so when I go to check into my flight in PER I will need to ask them to connect me and my bags onto this other flight to SG. Of course they will see I'm skipping my TPE to HKG flight that morning. That's the kicker.

So will they:
A) Cancel my second ticket?
B) Force me to buy a new ticket (with no open jaw)?
C) Make me land, clear customs and check back in (treating it as 2 separate tix)?
D) Be able to check my bags/tag them for the HKG-SIN in PER?
E) Be cool and just merge the tickets?

I know in the USA this is nearly impossible - the airline would try to have you arrested and hauled away in handcuffs, but CX is very easy going and generous to it's FF. I'm CX-DM

Grateful for any advice, past experience - need to book ASAP!