Phal in Recovery, may need extra advice? Two Large Leathery Leaves?

[Triffid]

~The History~
I acquired a Phal (Unknown but apparently has white flowers) over the Christmas season which had not been kept in ideal conditions.

It had been left in standing water on and of for about 9 months. Kept in a kitchen window which caught all the evening sun. Fed regularly on cacti food.

What I got was what seemed to me to have overgrown leaves, a bit of sun burn, and over 75% Root decay. Luckily no Fungus or pests.

It was Root hacked (only way! The offending roots were pretty much all black and squishy! Don't worry I used clean equipment.) leaving four stubby healthy roots which were formed at the leaf base. Re-potted and left on the dry side. New roots have appeared and are now growing. Some are now over two inches in length now and have a healthy thickness. Still a long way to go though.

After looking at other threads, I have now moved it to an even more less lit position than before (No I didn't have it in the kitchen). I had kept it in the Bathroom, hoping the air humidity would encourage new roots... Seemed to work.

~The Recent Concern~
Now, a concern for two of the older leaves. Since new roots started I continued to water as and when the roots started to become silver. However Two of the leaves seems to be dying back? Maybe? They weren't exactly great to begin with.

They seem overly large and leathery to appearance but has no discoloration other than the sun burn. The texture of the leaves is some what leathery, well like wrinkled skin. They have not yet reached that yellowing colour in any way, that a lot of foliage seems to get when it dies back. And even with a regular watering scheme the leaves do not regain that plumpness. Both are the oldest at the base of the plant.

I have had other orchids loose their leaves at the base, to be expected as the plant grows (I guess). But none of them acted quite like this pair? No colour change or that deathly thinning?

The other leaves are fine and plump and a new one even started to form. It started sprouting a new leaf bud about six weeks after I started it's recovery.

~The Question~
Should I be concerned? Am I just worrying over something perfectly natural?

Sorry no pics available yet.

Any tips, advice, comments, etc. welcome as always. Thank You in advance.

PS To all with sick plants out there "Keep Your Chin Up!"