THE QUESTION: When teaching wedding couples, must Waltz only be done to wedding songs in 3/4 time or is it "okay" to apply it to songs in 4/4 timing if its a one time thing?

CONTEXT:
I teach a lot of wedding couples, and often times they come in with songs that are in 4/4 time, so I just teach them the Rumba. The problem I run into though is the tempo is too slow, and even when I use syncopated footwork it becomes awkwardly fast.

Here are a few examples of songs I'm talking about:

• "What a Wonderful World" by Louis Armstrong
• "Thinking Out Loud" Ed Sheeran
• "Falling in Love with You" Elvis

I have transferred wedding couples over to dancing Waltz sometimes. My reasoning being I think the steady 123 footwork is easier for the wedding couple than whatever method of S-Q-Q I am having them do, but then get chastised by my coworkers because the timing is wrong.

I'm not seeking validation for my PoV. Just a larger consensus of opinions on either "Yeah, you can't. The timing must be 3/4" or "It's not correct, but it's 'okay'."