Cattleya dowiana var. aurea

There is definitely an accepted name Cattleya dowiana var aurea Bernard.

Cattleya dowiana var. aurea (Linden) B.S.Williams & Moore, Orchid Album 2: t. 84 (1883).
This name is accepted.

--------------------------------------------------------------------------------

Distribution: S. Panama to Colombia

--------------------------------------------------------------------------------

As to whether this is that variety others will no doubt help with confirming that.
I look forward to getting a result with this one.

PS: IMHO I think the type variety is superior

Look what A.A Chadwick has to say about C. dowina semi-alba:

"The extremely dark crimson-purple color of the C.dowiana lip itself appears to be tied to the white sepal-petal pattern because it only occurred in semi-alba varieties. No variety with lavender sepals and petals had this intense dark lip."

And more from A.A Chadwick about Cattleya aurea:

"Naming his new species Cattleya aurea, Linden explained in some detail in Volume I of his famous book, Lindenia, how to identify C. aurea and distinguish it from Cattleya dowiana, “the other yellow-petaled species.” The lip of C. aurea, he said, is a “striated yellow, bordered with crimson purple,” while the C. dowiana lip “is crimson purple with touches of yellow streaks here and there.” The petals of C. dowiana, he continued, “are often purplish yellow, or even dirty yellow” while those of C. aurea are “always yellow — sometimes straw yellow, sometimes chrome yellow, but always a bright and pure shade of yellow.”

This comment doesn't rules out the possibility to have a semi-alba with a pale pink color on the lip. But usually the semi-alba variety has dark lips.
In other Cattleya species the semi-alba variety also is restricted to dark colored lips. Whenever the lip is not dark or has a different color other than the type color, it is considered already an other variety as you can see on my Cattleya labiata and Sophronitis purpurata posts.

If it is Cattleya dowiana ou C. dowiana aurea it is not a semi-alba variety. As Bill mentioned it could be also a hybrid.
Horst