iOS “Add to Apple Wallet” PKPassButton layout guidelines

I'm working on an app that offers the functionality of adding a Price Card to wallet (just adding, no specific entitlements for updating or removing a passbook). The workflow from my app is the following:

  1. Present the price card screen where I have an
    Add to wallet
    button (Don't confuse it with the specific
    Add to Apple Wallet
    PKAddPassButton
    ).
  2. Press the
    Add to wallet
    button. This get's the pass package data from my
    API
  3. Build a
    PKPass
    based on that data and present a
    PKAddPassesViewController
    that enables the user to add/cancel the price card to the
    wallet
    .

I've followed the guidelines from https://developer.apple.com/wallet/Add-to-Apple-Wallet-Guidelines.pdf but they seem a bit confusing to me.My feeling is that there are two possibilities of adding a

passbook
:
  1. Add a
    Add to Apple Wallet
    button using the
    PKAddPassButton
    class and by tapping on it you add the
    passbook
    directly. (By using this method you are forced to follow the provided
    Apple
    layout for the
    PKAddPassButton
    ). By the way I tried modifying the standard
    Add to Apple Wallet
    button size but the layout just gets messed up.
  2. Get your passbook data, init a
    PKPass
    with it and present a
    PKAddPassesViewController
    that can Add/Cancel.

My question is if I'm supposed to use an instance of the provided

PKAddPassButton
for my
Add to wallet
button (NOT the specific
Add to Apple Wallet
PKAddPassButton
) or am I allowed to use whatever design i please being that the actual adding process is handled by the
PKAddPassesViewController
?

Another thing is that by using the PKAddPassButton the size is huge and doesn't go well with my layout. Can i create my own custom button by using the svg asset from https://developer.apple.com/wallet/ (btw the only available svg is for the two lines button please check https://forums.developer.apple.com/message/228903#228903) ?